So even if you had a buy out agreement negotiated up front and execute that buy out agreement, the bank would still require him to be guarantor unless something drastic changed on your side financially.The best scenario here would be to purchase and rehab the property using a hard money lender or bridge lender.  

Have you considered using a property management company?

@Nichole StohlerI find using a SDIRA to be a great tool for passive investments and growing your retirement with less stress than the stock market roller coaster. 

So more Roth for way less in taxable income incurred. doing this is easiest in a Solo 401k if you qualify but can also be done using a checkbook IRA as well. check out this post that @Dmitriy Fomichenko made explaining this concept.https://www.biggerpockets.com/forums/51/topics/1223601-how-t... 

It’s a great way to grow faster.HELOC or Equity Tapping: If you have equity in another property, using a HELOC or cash-out refinance could help cover the down payment without affecting your DTI as much.Seller Financing or Creative Deals: Look for sellers willing to finance directly, which bypasses traditional mortgage qualification hurdles.Scaling quickly often involves combining strategies—play around with what works best for your goals.

(If you are out of state, you may seriously consider using a good property manager because of screening tenants, vandalism, squatting, and various other reasons -- they do protect your investment).

About 6 months ago we purchased a duplex using a DSCR loan.

Also, after a year, the mortgage hasn't been paid down by much, especially if it's a 30 year mortgage.The only challenge you may run into is if you purchased it using a low or no money down mortgage option like FHA or VA lending.

I suggest using a service like Mayistay.

If done right using a hard money lender can be a great way to propel your portfolio with BRRRs.