Project cost is all expenses paid in the process of project construction, including the value of materialized labor and activated labor invested in project construction, as well as the new value created in the production process. Effective control of project cost is an important means of rational use of financial, material and human resources. Especially under the condition of socialist market economy, various factors of production and activities have entered the market one after another, and the value space for their own survival and development has been built through market competition. Therefore, how to scientifically choose the construction scheme, effectively control the project cost, and obtain greater economic benefits with less investment on the basis of ensuring the project quality is the most concerned issue for the construction unit. The factors that affect the construction project cost exist in the whole process of project construction, so the project cost control activities run through the whole process of project construction, from the feasibility study, scheme demonstration and preliminary design in the early stage of construction, to the construction drawing design, bidding, building installation and construction, until the project is completed, accepted and put into use. As the main body of project cost control, the construction unit can carry out active control activities in the following three important links. First, pay attention to improving the cost performance of the project in scheme decision-making and design. In engineering construction, scheme selection and decision-making are the most critical links to control engineering cost. Decision-making mistake is the biggest mistake, which will cause serious waste of funds; On the contrary, the correct decision will save a lot of investment and become the most effective cost control behavior. In order to make a good decision on scheme selection, we must establish the awareness of cost performance of construction projects, pay attention to the relationship between project function and cost, and choose the project with the lowest cost to improve the cost performance of the project. The original design scheme of the relocation project of Panjiakou farmers' market was to build a new road and enter the market from the market entrance. Due to the low terrain of the market, a lot of backfilling, tamping and slope construction are needed to build roads, and the cost of a road with a length of more than 100 meters is more than 30,000 yuan. In the discussion of the scheme, after repeated research and on-the-spot investigation, the bureau leaders made the right decision and gave up the scheme. Instead, repair the old road outside the west wall of the farmer's market and use the old west gate to open up market traffic. After the demolition of old houses, the cleaning of vegetable fields, the cleaning of garbage, the widening of local concrete pavements and the enclosure of green spaces, the corresponding construction tasks have been completed. This new scheme also meets the needs of goods transportation in the farmers' market, but the highway cost is saved by 80%. At the same time, it also solves the problem that private people occupy land for building houses and growing vegetables for a long time without compensation, controls the dead corner of environmental sanitation, and achieves the effect of killing two birds with one stone. According to relevant statistics, the influence degree of each stage of a construction project on the project investment is 75-95% in the preliminary design stage and 5-35% in the construction drawing design stage. Obviously, to control the project cost, the quality requirements of design work are not only reflected in the technical quality of the design project itself, but also measured from the cost performance of the project. Only a design that combines engineering economy and technology organically is a good design, and only a design that designers enhance their innovative consciousness and can control the project cost scientifically and reasonably is a design that the construction unit needs and is satisfied with. Second, strictly control the extra-budgetary investment in the construction stage, improve the project efficiency and complete the construction drawing design. After the bidding stage and the signing of the construction contract, the construction project enters the construction stage, which is also the execution and completion stage of the project cost. The space for saving investment during the construction period is limited, but there is a great possibility of wasting investment and expanding costs, so construction is an important link to control costs. The main task of the construction unit is to hire a supervision company with good reputation and excellent performance, sign a standardized supervision contract and assist the supervision. For non-external supervision projects, the construction unit usually sends on-site supervision by the engineering quality management department or the quality supervision representative of Party A to supervise the construction quality. When they go deep into the site, strictly check the quality and progress of the project, and find and solve the problems existing in the site, they should handle matters involving investment changes carefully. This requires them to understand the budget, be familiar with the quota subheads, work contents and related expenses, and avoid issuing visas that are duplicate with the budget. Timely and accurately measure and evaluate engineering changes, design notices, visas, material substitutions, etc. , strictly control extrabudgetary expenditures. Distinguish the responsibilities, and Party B shall bear the extra workload caused by Party B and the project cost overruns caused by material substitution ... For example, in the earthwork excavation project, Party B fails to accurately follow the construction drawings, resulting in over-excavation, which increases the workload of supplementary backfilling, transportation and compaction. This is obviously due to Party B, who can only bear the corresponding expenses and cannot affect the realization of the project contract period. In the installation project, Party B proposes design changes based on its ordering conditions, construction capacity, brand building, advertising effect and other reasons, and requests to improve the standards of certain materials and local building products, which will be implemented after Party A and the designer agree, so the increased expenses will also be borne by Party B. Third, strictly and accurately review the project budget, which is an important link to control the project cost. The audit of project budget and settlement should be not only strict, but also accurate. Only the strictness in the accurate sense is reasonable, true and feasible. The audit focus of project budget and settlement is whether the calculation of engineering quantity is accurate, whether the budget unit price is correct, whether the cost is in compliance, whether the construction claim is reasonable and so on. In practical work, due to personal interests or the quality of personnel, it is not uncommon for construction units to falsely report or misreport the project budget. For construction projects within one million yuan, the difference between the prepared budget and the audited budget (including the actual settlement) is about 200,000 yuan at most, and the reduction rate of the project budget is as high as 35%. To sum up, the following problems often appear in the audit of project budget and settlement: (1) There are many projects, and the projects that cannot be constructed actually are included in the engineering quantity. (two) repeat the content of the project construction. A quota has been set, and a quota of another different process or practice has been set for the same construction content, forming the same sectional project to calculate the cost twice. (3) expanding the engineering quantity. For example, in the earthwork, Party B will use the excavated foundation soil for backfilling, but in the budget settlement, it will be calculated that all excavated materials will be shipped abroad and the soil will be purchased for backfilling, which will increase the cost of soil purchase and transportation. (iv) Reuse of quotas. On the basis that the latter work has been included in the former quota, relevant quotas are set, resulting in duplication. (v) Quota error. Quotas of different construction contents or technologies do not match. (6) Raise the charging standard. E-class construction enterprises apply D-class charges, and D-class construction enterprises apply C-class charges; Four types of projects implement three types of charges, three types of projects implement two types of charges, and there are one or even two levels of contour sets. (vii) Increase the price of materials. The unit price of materials in pre-settlement is higher than the actual purchase price of the project. (viii) clerical error or complete error. The decimal point in the calculation of unit price and engineering quantity is misplaced, which leads to the increase of single cost; The total amount of a single page budget is greater than the cumulative amount of sub-items. (9) Recalculate the costs of spare parts and materials that have been included in the sub-projects investment. In practical work, the budget not only often appears the phenomenon of over-calculation, over-calculation of expenses and increase of costs, but also occasionally appears the situation of low budget. Auditing the project budget and settlement should not only reduce unreasonable expenses, but also make necessary supplements and improvements to the missing items and budgets caused by work mistakes or insufficient professional level, so as to meet the necessary funds for the project, protect the due interests of construction enterprises and ensure the project quality and construction progress. To sum up, controlling project cost is a comprehensive system engineering integrating management, technology, quality and construction. The construction unit is required to effectively control the use of funds within the scope of their respective duties, from the top leaders to the professional and technical personnel. In order to continuously improve and effectively control the project cost, the construction unit can also learn from the following practices: (1) carry out the training and assessment of project cost professionals, combine the assessment with daily management, and accelerate the improvement of the professional quality of project cost professionals; (two) according to their own characteristics, formulate a systematic and scientific project cost management system, and form the coordination and unity of planning, design, quality, construction, management and other departments and units.