A couple of factors are at play.First, rents trail purchases because it's a less efficient market. 

I'm not factoring in appreciation, equity, or 1031 exchanging into better properties, rent raises, or promotions at work, so it can go more quickly than that, especially if I can figure out ways to use OPM so I can scale more quickly.But, similarly, appreciation would mean that acquiring such houses would take longer, and that's assuming I can find properties that actually cashflow $300 after everything, including capital expenditures, repairs, etc.

What size is the multifamily, this could play a factor.

I am not sure why rebuilding as a single family if destroyed makes a difference since my mortgage broker confirmed I would qualify for the property without factoring in the rental income (i.e. if this was a single family at the same purchase price I would still be able to afford the property).

If you did, I would consider this a sunk cost and not relevant when factoring to sell and the 'ultimate loss' you will incur. 

We could scrap half of the laws in place and utilize technology so much better to help customers as an industry (speaking as a direct lender).I’m doing almost all of my company’s closings without external appraisals because it’s taking months to get them back.

I wish you well but I'm curious how this factored into your decision? 

You could keep them on your computer, backed up on an external hard drive or cd/dvd/flashdrive. 

Keep in mind you should still account for maintenance, capital expenses and future improvements (which are all accounted for in commercial property along with vacancy factor)I know this is a lot of information but success is in the details.Final point, if the numbers are right this property should qualify for rehab and long term financing.

The BRRRR factor in my thought process is that leveraged more quickly. i.e. with option 1) buying more turn-key properties without forcing appreciation and refinancing (BRRRR)...it may take me many times longer to acquire the same value/# of properties, vs using option 2) the BRRRR method.