Offering under asking and for what we saw as an appropriate price for us.

If she wants it, make her pay for it appropriately.

On a 30 unit apartment complex, even just moving that much paper around could be problematic based on scale and amount of time committed to the plan.Your analogy of selecting which stocks to buy/sell is appropriate. 

SIde B gradually gets to market rate (always informing tenants appropriately). 

Much of what you're looking for can also be required during your inspection period and if you take the appropriate steps to perform due diligence you would ideally uncover and major potential problems and at that point could cancel your contract or renegotiate. 

@Scott Mac I will definitely dress appropriately for the occasion and ensure that I present myself in a professional manner.

You won’t be able to price it appropriately without talking to some commercial brokers and/or costar.Commercial properties are valued differently.

If I can negotiate a more appropriate price, what are some methods by which to finance this deal?

If there was a lease in place, you respect the terms of that lease for the rest of the lease period, and in the appropriate time before it expires, give them your lease, along with a rent increase if indicated.   

These moms see it as their right to move their adult criminal sons in, who we are appropriately terrified of.