Some municipalities do have an extra transfer stamp tax which can be frustrating when people sell, but that has nothing to do with whether or not you are taking money out of the state. 

Major changes will require architectural drawings and possibly an architect or engineer's stamp. 

They come with a special stamp in addition to the data plate. 

My issue with BRRRR is that there are significant transaction fees, closing costs, stamp taxes, etc every time I refinance a property.

You’ll have to pay for closing costs, doc stamps, funding fee, origination, etc.

It gets time stamped and there is no excuses like “I tried to get it to you but you weren’t there”...And having odd dollar amounts for rent eliminates the hesitancy to raise rents annually as well....

Are you using bulk mail or 1st class peel and stick stamps?

Syndications have a time stamp.

The architect can determine if any structural work needs done, and have that piece designed and stamped by an engineer and incorporated into the plans.It sounds like you will definitely need a permit.

Take a video walk through of the house and narrate it as you go, pointing out any and all damage and wear no matter how small,   Take lots of pictures too, especially of any damage you do find (turn the date stamp on for the pictures if you can).