However, I get people asking for a monthly rental all the time, so we offer it with a 25% increase to the normal rent.

Which of the two, SBA or commercial loan, offers the best terms?

Remember, your day-to-day costs have increased, but so too have your client's.I work closely with an STR investor that just began offering co-hosting for AirBnB. 

Private money lending involves using your own funds to finance real estate investors' projects, offering interest rates of 8-15% with terms of 6-24 months.

I work with a good amount of investors, and some advice I would offer is to not shy away from a deal bc it is not a "perfect" BRRR.

Can you please let me know which lenders offer this option?

You can refinance a DSCR loan but not on a specific timeline depending on the loan you choose. 

Many lenders, including my group, offer a DSCR product to refinance on the back end as well.Before taking out a loan for a BRRRR project be sure to calculate all carrying costs (taxes, insurance, utilities, HOA, loan interest, etc.) to ensure (i) you have sufficient cash to cover monthly payments for at least the duration of the project and (ii) your estimated rent after repairs is at least 1.10x PITI (monthly refinance loan payment principal and interest, taxes and insurance).We have a proprietary BRRRR cash flow calculator tool that we share with our clients to help reliably assess costs and returns for these types of projects.

Offer to pay the tenant $200 to be out by midnight tomorrow and never be seen again.

The specific location ( 4' * 6' long) is underneath a guest bedroom window in the front of the house.