(b) At the time that the subdivider makes an application pursuant to this division, a local agency shall determine whether or not it is able to meet the time limits specified in this chapter for reporting and acting on maps. If the local agency determines that it will be unable to meet such time limits, such agency shall, upon request of a subdivider and for the purpose of meeting such time limits, contract or employ a private entity or persons on a temporary basis to perform such services as necessary to permit the agency to meet such time limits. However, a local agency need not enter into such a contract or employ such persons if it determines either that (1) no such entities or persons are available or qualified to perform such services or (2) the local agency would be able to perform services in a more rapid fashion than would any available and qualified persons or entities. Such entities or persons employed by a local agency may, pursuant to an agreement with the local agency, perform all functions necessary to process tentative, final, and parcel maps and to comply with other requirements imposed pursuant to this division or by local ordinances adopted pursuant to this division, except those functions reserved by this division or local ordinance to the legislative body. A local agency may charge the subdivider fees in an amount necessary to defray costs directly attributable to employing or contracting with entities or persons performing services pursuant to this section.