I would either use a HML spread over multiple deals to rehab or I would find a property with good bones (foundation, and most studs/joists are solid) then buy it for super cheap and force appreciation through the rehab, which is what I do. 

Biggest thing is going to be structural or foundational issues as long as that is solid it's okay.

Hi there,It’s awesome that you’re taking the leap into real estate investing, especially with such a solid financial foundation.

Your experience in managing investments and projects, like your mid-term rental in ABQ and the condo development in Mexico, will surely give you a solid foundation as you delve deeper into real estate with a focus on cash flow.If you ever want to chat about strategies or need advice on your next steps, feel free to reach out.

We got our own excavator which saves about 10k on lot clearing and foundation prep. 

You don't need to know everything to get started; you need a foundation to build on, and the rest will come through experience and then refining your education.You can build a basic understanding of investing in 3-6 months.

It is hard because you feel like you are falling behind, but you are so right that I need to ensure that my foundation is stable.

If the tiny home is more like a medium home (600+ sqft) on a foundation, then you should be able to look at it as a "stick built" or normal home, just small.

Has anyone had experience with purchasing or considered purchasing a building with a sinking foundation?

From the floor joist being cut from the sill plates and the entire house needing brought to level, the foundation requiring correction, to the no slope rubber roof leaking and needing replaced when I say I renovated every square inch of this property I mean that literally.