A lot of what you can do is dependent on the zoning, codes, laws and regs of the local and/or state authorities where you are building.

My wife and I bought 2 acres and put up a manufactured home in 2007, just before the bust. Call it a double wide if you like. A nice one. Paid a lot less than we could have - we knew the bubble was about to burst and we had plans for other stuff besides a big mortgage. Lots of bad stuff has happened since, but we still have it. Never regretted the choice, Would do it again today. Had we gone for the McMansion, we'd have been done for.

Find out what the options are. Pole building? A shop building with an attached living quarters? A gently used quality double wide? Small manufactured house?

Housing market is a mess now. Materials are high and scarce. Existing homes are crazy high. With the current situation, I would recommend, first and foremost, do something that you can afford, even if the wheels fall off and things go completely sideways for you.