With the right survivors that have the appropriate specializations, you can repair or upgrade parts of the map to give a benefit. Repairs usually come in the form of donating resources like Supply Rucksacks or Fuel. Different specialties can cause the price to be cheaper, or open up alternative payments. Computer Specialists might allow you to use Circuits instead of Parts for example.
Things that can be repaired are things like the street lights in a town, allowing better sight at night. A broken bridge on one of the maps can be repaired for a much needed shortcut. (Pst... break the bridges randomly on a new map start) Water canals can be drained to reveal new items or trapped survivors. Car pile ups on the road can be cleared for easier driving. The limit is your imagination, UDL.