You may have come up with an idea, but for others that may need it, and may have been said before, so I am just agreeing with those that did.....you answer is right there.
You have a town in disarray that needs help to get back on its feet. You wouldn't as the adventurers to become carpenters, though you could and some might like it, but you could have the locals do repair work, while and local authorities were doing that the town needs some work-for-hire guards and such as the town rebuilds and restructures. depending on if the town was raided or being controlled through leadership puppets, etc.
Nothing wrong with adventurers up and leaving after doing there job, but the town could offer them various other jobs while it gets itself self-sustaining again.
Not all of that even has to be played out, you can just handwave some activities where guard duty for a week passes and payment is made an onto the next job. An adventurers life isnt just killing and capturing, that would be assassins and bounty hunters.
You just need to find the right vise for the players to give them reason to want to stay and help this town.
