I am trying to calculate my returns over a 10-year period using the rent-by-room strategy, which results in significantly more cash flow than traditional rentals.

Banks who offer construction financing tend to be 75-80% LTC and alternative/hard money lenders will sometimes offer higher LTC leverage than that.

I bought it because it was supposed to be easier to keep up with than traditional, but I've had to rebalance the ph myself several times.  

They wanted to see the cash in a bank account or statement.

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.  

I do not have a traditional W2 job so I can't pursue the typical conventional loan or a FHA since I don't have income (hence the DSCR route).However, I've seen that most DSCR lenders do not lend if the loan amount is less than $100K.

It was 20% down  Like I mentioned on my comment above, it is possible to still finance this property with a non-traditional lender, especially when you are putting 20% down.

Most traditional property managers don’t handle this setup due to challenges like managing tenant disputes, coordinating overlapping move-ins/outs, and the risk of Fair Housing violations when selecting tenants.

Traditional 30 year fixed mortgage How did you add value to the deal?

In theory it would be wonderful to get mortgages at 3.5% down and search for value-add deals to near break even on cashflow after year 1-2, banking on appreciation from a highly-leveraged investment in a growing economy.