Account ClosedI would let the tenant know that you will enforce the terms of the lease if the unit goes vacant, which means either he or his company pays the rent through the duration of the lease until a suitable tenant can take his place.

Typically there is an occupancy clause in a mortgage that requires the borrower to live in an owner-occupied house for a certain duration.

I typically look for 15% of ARV, with a minimum of $15K.For simple projects, I might take less; for longer-duration projects (new construction, for example), I'll look for more.

I agree that 15 or 30-year financing from private investors is asking for trouble unless there is a balloon to reduce the duration.

If you are going to subordinate the lot only then a fair split would be retail price for the lot plus a premium that would represent a reasonable interest rate for the duration of the project. 

Usually furnished and for 3-6 months and rents are at a premium both for the short duration and for the furniture.

You believe you are "paying the lender back" (to use your words) the $766,440, when you are really only paying back the original loan amount of $320,000 PLUS you are paying $446,440 in interest over the full duration of the loan; you can reduce that interest total payment if you do any sort of pre-payment of principal. 

I think the benefit of property management is does produce  a steady stream (for duration of contract) of additional income for your business.

That reaction and their ability to handle surprises will be the same for the duration of your relationship.  

We may find out that we need a 45 minute or 1 hour time block duration if we regularly exceed 30 minutes (especially if we experience vacancies, several maintenance requests, or if we accumulate more rental units)This will hopefully allow us to organize our time, communicate better, and get more things done.