.- First Rule: you buy the materials, so they don't need 50% down!

Insurance companies are taking a close look at building materials, quality, and updates. 

You may be able to lean on the title company if they missed something, but generally if the deal closed and its not an issue of material disclosure or title or something its generally your issue now, the owner doesn't really have an obligation to comply if they closed according to the CD you signed.  

My question is, do I just use the heavily reduced price I was able to purchase it for since it was vacant, and then the material cost of what I renovated plus what things I did contract out, even though that basis would be way under what the other renovated houses that sold near me per SF sold at, or are you able to use similar comps to determine the depreciation basis?

I'm debating sponsoring other areas to hang my material up.What ways do you like to promote your business?

Estimated CostsADU costs can range DRAMATICALLY depending on the state of the lot, custom vs fast track plans, size of ADU, materials and finishes, speed and quality of the builder, etc.

Good call, Noel—licensing and insurance are critical, but in Tennessee, a contractor’s license is generally required for projects totaling $25,000 or more, including labor and materials (See Tennessee's licensing requirements).

@David Pike For what it’s worth, I was on a call this evening with a very experienced real estate investment company who stated they don’t expect any material reduction in interest rates for extended time period.  Based on their long-term track record, I would think their opinion is as good as any and better than most.

I own a licensed gc company so if it is in a decent area I know I can add alot of value to it at a cheaper price since there won't be any labor or material markups.

I would assume a greater emphasis on quality of materials and workmanship (and consequently higher rehab cost) for a rental where the investor will have to deal with the longer term implications of any corners that were cut.