1, high amount, long cycle: engineering projects usually involve a large amount of capital investment and a long construction cycle, so the payback also need to have a certain cycle.
2, progress payback: engineering projects are usually in accordance with the different stages of completion of the payback, according to the progress of the project and acceptance, payback in installments, this way can control the project risk, but also increase the uncertainty of the payback.
3, payment security: in engineering projects, it is often necessary to open a bond or warranty to protect the process of payment and quality issues, these additional costs also need to be taken into account.