I would think that if the tenant is paying for the addition, they would want to have a minimum of a 5 year lease, if not a 10 year lease in place in order to pay for the improvements.As in any real estate investment it is risk reward, I think with the current market and a stable vet tenant, that if you can get a 5+ year lease, it would be worth it to let them expand.If you are worried about value, you could always talk to a commercial real estate appraiser.

Some DSCR lenders will float the rate until the appraisal is back, leaving you open to having the rate changed during the floating period.    2.

(We're aware of the five year look back period for Medicaid eligibilty but it's not a big factor in our decision to do this.)We would get the house appraised so we can document paying FMV.House would be purchased with cash (it's a small home in a rural area and value is low)Inlaws would sign a lease so that it becomes a legitimate rental and we can deduct expenses, etc.

Search the BP for ADU appraisals to encounter numerous examples.

Services you cannot shop for seem high ($800/appraisal - is this a rural area)? 

I explained to the seller that my offer contained a substitution of collateral clauses and I would be exchanging the note they held on the subject home with a note of similar principal and interest secured by a different property of greater appraised value.

If you want to do BRRRRs, it's probably better to stick to B or better neighborhoods, as they appraise better and have a higher likelihood of getting your equity out!

Because he/she will know the process of buying / selling properties so they can be better suited to ask you the right questions.For example, since I acquired properties in the past, I know the ask clients if they got a home inspection/appraisal / survey prior to closing on the property.

If I refinance, I can wait for a few months to see if the rates go down, but that would mean that each mortgage payment I make would benefit my ex as he gets half the equity in the home at the time of selling or refinancing based on an appraisal.

There is a good chance they would limit the loan amount based on either appraisal, or purchase price + improvements (ie project cost), whichever is lower.