I requested the lender to explain it and stated that they are not sure why it was quoted at the lower rate but the actual amount is the increased rate. 

Regarding the bank time-frame and refinancing, banks will always loan you money--until they won't!

I have a duplex that has long term tenants in the upper unit and the lower unit has been short term rental (Airbnb).

The depreciation is taxed at maximum 25% or lower based on your marginal tax rate. 

Allentown and the Lehigh Valley would be convenient, allowing you to see the properties you are buying, meet your team in person, and have a lower price point then Philly.

Have you considered an FHA loan, or other facility that requires a lower down payment?  

There is just a little less room for error when dealing with a smaller park as you don't have as many lot to absorb a vacancy or an increase in water usage(even if you can collect)..or some repairs to do etc.Good job on negotiating them down so far...for me i will still have to go lower and look something like this....200*18*12*.5/.1=216k purchase priceI prefer to pay lower than this based on a smaller park and limited upside potential based on your observation of market lot rents.  

I can't promote myself a FL Mortgage Broker on this site, so instead, if I were you, I'd look for something like a Stated Income ALT investor loan in the mid to upper 4% to lower 5% range on a jumbo loan at 75% ltv on a 10/10 arm, 300/240, no escrows and no PPP.And remember, use other people's money to make money!  

The sellers had high equity (they lived here for 25+ years) but low personal cash, and they needed the fast close to get the cash to purchase a home in a lower cost of living area.

Alternatively, you could buy an apartment building with a lower deposit and reach your goal even quicker.