Are you open to working with contractors, or do you stick with established businesses only?

Built in a factory the quality is often better and cheaper than stick building out in the elements.

I am wondering if prefab or stick built would be the way to go.

Don't split the work between multiple contractors if possible, finding one to do all or most of the work will keep prices down.Challenges were finding replacement pieces for certain items as manufactured homes were very different than stick built as well as going through state guidelines for affixing the house to the land

I currently have around 100k tied up in sticks right now which I would prefer to leave in and just continue to save with the plan of getting a place in the next few years, I would get a second job to raise the funds.

My biggest sticking point is they have severe weather; floods, hail, tornadoes, etc.

STRs are also not my game and I prefer to stick with what I know. 

I don't mean to be a "stick in the mud", but successful SubTo is treated very differently than a bank loan investment property.I've done Subject To for a very long time, been sued over some pretty ridiculous accusations and have had to sue to clear up title.

My main question is whether it makes more sense to go the seller financing route and pay off the principal in 8–10 years or stick with a standard 30-year loan.My thinking is that the tax deductions from a mortgage wouldn’t outweigh the potential equity I could gain over those 8–10 years.

If the drywall cracks in the next year or two, or the doors start to stick, then you likely have a larger settlement issue going on, and will likely need to call a foundation repair contractor.