You will also have ADA issues with all stairs only access.

It is not at all unreasonable and I like it.  

That would be our second goal of getting into BRRRR.I would like to meet people in areas that have all the tools that I do not… which is basically everything.

I suggest you contact each of your tenants currently renting at 721 to determine who all intends to stay and who is planning to leave.

She has handled all the interior design . 

However, I was curious to know if anyone has looked into how treehouses appraise, if at all? 

I have hit up some agents, but they all just sign me up for their OneHome (or other MLS notifications) and I don't feel like I'm getting anywhere with those.

That said, if I was retired, in a relatively low income tax bracket, or a real estate professional able to offset my commission income and interest income from PML with major cost-segregation, and wanted some spendable liquidity after a career in investing - PML all the way. 

I think it all depends on your situation.

The office administrator did the initial due diligence, the corporate counsel reviewed the lease, the accounts payable coordinator setup the accounts and sent the security deposit, one of the VPs signed the lease, and only after all of that occurred did I get the name and contact information of the tenant.- Now I am in their system as a Vendor/Subcontractor.