I want to get rid of the PMI as well as locking in the lower rates of the current market before rates start climbing too much. 

In my case, the buyer is the owner lock, stock and barrel.

Most loans are lower than inflation, and in 5 years when you're about to pay it off, you're still paying on the today's value of the vehicle, not the inflated value of the vehicle.Look back at car prices from 5 years ago and ask yourself if you would like to lock in the 2010 new price on a 2015 car... that should answer it.

Will provide lock box code.

If the house is vacant there should be a lock box. 

Computer is backed up monthly, all files are in locked cabinets.

But by the time the newbies get a chance to even look at something on the MLS it's usually already locked up by them "wholesalers" lol if its a good deal! 

Profit is locked in the day you close escrow ... you may not realize the profit at that time, but if profit is not "baked in" with a high degree of certainty at that point, it is not an investment IMHO.

I'm trying to lock up this property, but I don't know how much other developers would pay for it.

The tenants are not locked into a certain rate and you can raise the rents.