(a) Without complying with the competitive sealed bidding procedure of Chapter 262, a commissioners court may make a contract with a developer of a subdivision or land in the unincorporated area of the county to construct public improvements, not including a building, related to the development. If the contract does not meet the requirements of this subchapter, Chapter 262 applies to the contract if the contract would otherwise be governed by that chapter.
(b) Under the contract, the developer shall construct the improvements, and the county shall participate in the cost of the improvements.

(c) The contract must establish the limit of participation by the county at a level not to exceed 30 percent of the total contract price. In addition, the contract may also allow participation by the county at a level not to exceed 100 percent of the total cost for any oversizing of improvements required by the county, including but not limited to increased capacity of improvements to anticipate other future development in the area. The county is liable only for the agreed payment of its share, which shall be determined in advance either as a lump sum or as a factor or percentage of the total actual cost as determined by an order of the commissioners court.
(d) The developer must execute a performance bond for the construction of the improvements to ensure completion of the project. The bond must be executed by a corporate surety in accordance with Chapter 2253, Government Code.
(e) In the order adopted by the commissioners court under Subsection (c), the county may include additional safeguards against undue loading of cost, collusion, or fraud.