Money is essentially made up in a campaign (how much gold does the dragon have?!?!?). It would probably be more fun for the players if they had to quest to get artifacts to draw people to their town. Or had to quest to find and hire someone of sufficient skill.
Guilds regulate the quality of a good
Anyone can hammer out a sword, but only a black-smith with level 7 certification in smithing can make a "Combat Approved" Sword. Do you heroes want to risk a cut-rate smith when the Goblin King is staring them in the face? Do they want their product's reputation to go to crap because their blacksmith didn't have the certification he said he did?
The leader of the Guild must visit your town and verify the swords produced will be quality. A Lich King that has been disturbed by the new forge could make certification difficult!
The scholar is looking for a nice place to settle down where he can have a nice house and a big back-yard. But he also wants a library and a sphere of seeing so he can stay in touch with his friends and family back home.
Those Spheres only grow in the deep dark cave. Adventure Time!
Looking to Start Over
The new apothecary was caught making some "Good Time" elixir and selling it under the table. Word was he also might like to have a little of it himself. He's a nice guy who just wants to start over in a new place.
He also might think it was really funny to spike the Solstice Festival drink with some Party Potion - with unpredictable results!
People spend a good amount of time in their real-lives figuring out price-vs-value. It's not usually the fun parts either.
Do you by the low mileage Toyota, or the high mileage Mercedes?
Do you take a fancy consulting job that pays well but means traveling every week or do you keep your current job even though you're budget is a bit tight?
Don't make your characters haggle over stuff like this - it's not fun.
EDIT (in response to comments):
Unless the players are economists (and will have fun arguments over this decision), you're probably better off just choosing an NPC that is near the player's level and letting them occasionally get free/cheap armor upgrade.
I've found that money is usually the least fun thing to role-play as no one ever wants to game as "Phil from Accounts Payable." They want to be "World Class Theif Treegen (who has sticky fingers and a heart of gold)" or something like that.
Realistically, will you ever not let players go to the pub for the next quest because their account is overdrawn?