I like doing projects around the house, and I know my wife loves making houses cute and she has great interior design tastes. 

The BRRRR method is designed to help with the very problem you are describing.

It starts with a self-directed IRA held by a custodian, but the IRA simply makes one investment into a specially designed LLC entity.

I designed spreadsheets strictly for plumbing & HVAC services.

You can check out SKSI & Maxable for design and Greatbuildz for contractors/blogs on ADUs.

(If you plan on taking in nothing but accredited investors the 506C designation is what you're looking for) and just produce one master ppm which just really defines everything about the fund except the project?

In your experience should I hire an architect, designer or a draftsman.

Extra tips:  Fiverr.com is great when it comes to stuff like flyer design, email signatures, etc. 

You can find free ones from the State of Utah, but they are not very well written and are designed to be as unbiased as possible, if not, favoring the tenant, which isn't what you want.

If you ask an insurance agent they will tell you to buy insurance out the wazoo.I think the asset protection mantra pushed on landlords is solely designed to make money for lawyers, insurance agents and asset protection gurus.