this is what I'm trying to say. The suburb next to mine happens to fall into another city, their city went "broke", my friend has a 60 yr old very tiny home and pays almost as much as i do but does not benefit from the same things, good schools, town upkeep- roads, snow plowing, etc, crappy library, etc. Buying a home just a few miles from me, results in a totally different picture without lower costs. IMO, most realtors are not upfront about this stuff, try to ask people you know there or meet potential neighbors, see what they have to say, read the local paper of where you want to go for a while.
honestly, the situation you have with your sister sounds sweet, you can't get much lower than that. If you have a good relationship, of course. Now that I'm older, I would love to live with my brother, he drives me nuts but I love the fool and a few years of co-habitation would actually be great. 20 yrs ago, there was not enough money in the world to live with him. Can you renegotiate the cleaning fish deal? If you're paying your fair share, why should you be treated like a kid about the fish stuff? As long as you clean up, why do they care? This sounds like the cheapest option that might allow you to sock money away for when you do know exactly what you want.
Are you already in a gov't job that will help with your student loans? Because that sounds pretty critical. If you already are, wouldn't you want to stay relatively nearby to get that loan deal? And if you're not already in the right job situation for this, wouldn't that decision need to come before you choose where you live and maybe end up somewhere that does not have a gov't job suitable for you? So I think I missed a post because I can't tell what the deal is on the job front.
kudos on paying off car, ex-wife, etc