There is always a chance that rates will drop, but I would imagine $25K would buy down the annual rate so significantly that you would never see a lower rate offered by a bank so you wouldn't even think about refinancing.

The rates on the 4 unit are astronomical even compared to what the current owner is paying (about 190/mo).

Rate should not exceed 12.5% at most and more commonly about 11.75%.

I think (not sure) its relevant to my bond rating.

This results in lower vacancy rates and better tenant retention.4.

Any help on how to figure out a local CAP rates for a specific area would be helpful.  

The more complicated your business structure becomes, the more problems it can actually cause such as when looking for lending options, getting the best interest rate, keeping clean accounting, filing taxes, opening bank accounts, getting credit cards, executing a 1031, making title insurance claims or even triggering a due on sale clause, etc. 

I expect that we will experience another period of extremely low interest rates due to Govt intervention in economic crisis to prop rates. 

You probably can't change the rate by much, you can raise it some if you include utilities.

Those programs may also have a list of lenders with better programs or rates for first time buyers.