On the complete team thing. yes it does exist BUT it's VERY rare. 

DOES THIS EXIST? 

Keep in mind rent control is 1 thing, its a laws for existing tenants but some city's like Newark are so strict that you must get approval for what rent can be even after a tenant moves out and new ones move in. 

They are hard to find, but they do exist.

We were in a financial position where we could keep our existing home, upgrade, and purchase another home.

With existing tenants, you DO KNOW THEM!

I have seen some properties on MLS that I contact my realtor and they may know right away the reason it isn't selling from showing it previously, or they can review the realtor comments that aren't viewable by the public on MLS.Other potential reasons I have seen properties listed on MLS for a long time. 1) Some investors may not be comfortable inheriting existing tenants.2) It may be it is a class C neighborhood. 3) Structural issues.

The type of information needed depends on if the building is being constructed in the future or if the building already exists.

To get to the ARV of $250,000 , I am assuming as follow:Because you spent $15,000 in renovation, I am assuming you increased the Initial value of the property at 30,000 bringing it at $230,000Add a 8.69% home appreciation for one year $20,000Estimated Home Value After 1 Year:$250,000Refinancing Breakdown:New Home Value (Post-Appreciation): $250,000 New Mortgage Amount (80% LTV): $200,000 Existing Mortgage Balance after 12 months: -$158,035 Assuming 3 Months Interest Penalty for Breaking Existing Mortgage: - $2371Total Cash Pulled Out: $39,594, allowing you to recover to pay a portion of your initial investment of $63,548, leaving $ $24,015 in the deal.Many new investors mistakenly believe the BRRRR strategy ends after the cash-out.

Are you aware of city of San Diego rules regarding converting existing legal space to ADUs?