Miss. Code Ann. § 53-5-21

Payments to the agency or agencies making the surveys authorized in Section 53-5-17 may be paid during the performance of the survey. However, the total of such payments shall not exceed ninety per cent (90%) of the estimated total cost until after the survey or surveys are finally completed and formally accepted by the governing board or boards having the survey made. Payments may be extended over the term of office of the governing board or boards having such surveys made.