We turn them around or help the owner sell the real bad ones.

Your wife as conservator/guardian has an obligation to her mother and selling the property to herself creates a conflict of interest in that she stands to benefit as the buyer and is also making decisions for someone else as the seller.2.

The owner has taken it off market and I'm just trying to explore my options of selling it off market for a deeply discounted price.  

It's hard to harvest equity on these plays, unless you commit, long-term, towards very light leverage, as the only practical ways to benefit from the equity in your portfolio, if you plan to never sell it, only exchange it, for a lifetime, are to spend the cash flow, or cash out refi.

If you have to do an ARM, have a Plan B to pivot if you need to sell or refinance. 

In early 2023, we decided to sell the property as the market had appreciated significantly.

There is a problem, but they always need somewhere to go and will never sell until that is clear and the path is set.

Is it possible to sell or refinance one unit to pay the other off completely. 

A co-worker of mine is selling her condo (which is not listed on the market) and is allowing me first dibs. 

Let's say you did buy the property and the students decided to pay the rent and everything was great... would this property have a good exit if you needed to sell it like this?...