
First of all, the town would have to be cleaned up. After that, you start out with 2 basics choices: Become the mayor of the town and continue fleshing it out, or handing it over to the NCR for an instant reward, a couple more follow up quests/things, but other than that losing control of the town. There might be another faction you could hand it over to as well.
If you become the owner of the town, there's a lot that needs to be done. A few buildings need to be repaired so people can live there. Caravan groups could be talked to so that they put Nipton on their route. Trade agreements could be made with Novac and Primm. The town needs its defenses upgraded to protect it from hostile factions trying to take it over.
Once you've got the basic living conditions down, there should be more customizable elements again. Like, what kind of town is it going to be. Here are the town types I had in mind.
-Trading/Farming town
-Casino/entertainment town
-Slavery/Small Industry town (Comparable to 'The Pitt', basically, but more simple)
After that you can base your decisions of what you want to build/arrange, and in what order, based on how the town is doing. You can't build a large casino without investing in some kind of security first. If you want a decision that the Nipton residents might not agree with, you'd better make sure they are pretty satisfied with how the town is first.
Most of the town specific stuff will be placed in the town hall. The top floor will be for you (and your advisor guy, who carries out your decisions for the town), but the other floors could be turned into a casino, or some sort of workplace for slaves, or maybe a meeting spot for traders. Most of the generic Nipton houses will be a place to live for the new Nipton inhabitants. But one could become a medical clinic or a jail, etc..
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Feedback is appreciated.
I'm currently working on the first security part, which follows after the initial cleaning and just before you decide what kind of town Nipton is going to be. Any suggestions as to where the Courier would be able to find people willing to work as a security guard in Nipton?