I think Brandon Turner said it in a podcast, but you could ask for contact info for the last two landlords to avoid the problem you described.

It will describe the boundaries of the unit. 

However most of us would not want to live in a building as you describe and would not want to be involved in what the landlord would be expexting, especially off duty.

What this lender described is a typical loan scenario for commercial loans - amortize over 20-25 years, with interest rates adjusting every 5 years.

1) if the MLO has  any  inkling the  borrower  may payoff the loan  or sell the property in 6 months - they should avoid  using any srp  pricing   and  explain to the borrower as to why   (  of course - this likely defeats  the  benefit to the  borrower for  doing the loan ) 2) if the  borrower  has  some control of the  timing  on paying off  a loan  ( aka - they  sell another property and  have   cash to  use to payoff the loan )  ...and the MLO becomes aware ......ask the  borrower to  delay paying it  off ( if possible )  until after the EPO 3) Do answer the prepayment pen  question the way you describe  4) the EPO  that  come  out of the blue  especially  when a  recent loan is  refinanced  by another  company are the  worst ones to  deal with and  unfortunately  there isnt anything that  can  be  done to avoid these  situations fyi - most epo  periods are    approx  6 months  but there are   some that are  slightly  different  in timelines  ..eg.  6 months from  1st pmt due date ....6 months from when servicing is first sold  ...etc

Describe exactly what you described here seems pretty credible to me.

@Alex GuerreroA couple worthwhile things to think about as you describe your scenario:1.

There are some companies that do asset based lending that you describe.

(ii)ExceptionsThe term “period of nonqualified use” does not include—(I)any portion of the 5-year period described in subsection (a) which is after the last date that such property is used as the principal residence of the taxpayer or the taxpayer’s spouse,

You want to find what references describe what the casita is (I assume an accessory to the primary SFR use) and then find other accessory to a primary use such as a detached garage or pool etc.