The agent told me it is a pain to move a post office and no benefit for them to sign up for the extra work involved. 

This is inclusive of disposal fees, permits to remove, air studies, etc etc. 

There is a reasonable chance that you could be required to convert it back to a 2 bedroom, so you would have paid for the extra square footage I would expect to pay for the original square footage and have the price discounted from that for the extra hassle and risk of dealing with the code enforcement officer 

We have 2 br condo builders here in Silicon Valley do not even provide a.c. for condo at 1.8M, 1.7M 3 br, 2 bath 1400sf with no balcony or ac(extra) under high voltage power tower.

Section 8 is a great way to earn extra cash flow, and as previously mentioned in lean times, that is great.

Permits have been issued with blue prints available! 

It's not hard to do and I like that extra 10% rental income. 

Not only are you creating a lot more work for yourself but you’ll also need to pay to open and maintain those LLCs to your state and CPAs will typically charge extra for an entity tax return.

Lyft, Postmates, Grubhub, etc. and earn that extra money and pay everything off instead of BKing.

Leading up to purchasing my last house I paid it off weekly.  ...I don’t know if that even mattered but it satisfied a concern I had and didn’t cost me anything extra other than a few seconds of time.