I would really appreciate some help in analyzing this deal so that I can make a better informed decision on whether to pursue this property or not.

This is not easy to do and requires industry knowledge, but it is more profitable in general.  

While it's almost never worth pursuing past rent, it enables tenants to keep doing this to other landlords.

We took a sad little building, and now have a pretty, friendly, profitable community.  

If its a for-profit developer, as Wayne suggested, they're likely to be trying to build for highest and best use.

Let's say we find a project "pay cash" and do a rehab funding it with our credit line, then turn around and sell it for a profit, pay down the credit line and square up on that.

We were fortunate to be able buy it low enough that we can afford to do this and still make a significant profit. 

I mean by adding one bedroom to a previously existing 2 bedroom and adding one bath I have successfuly turned a $150,000.00 home into a $300K plus home several times so in my case it did prove to be profitable  but timing is everything and so is location.

We've been pursuing MHP's for about 10 months and have two under contract. 

You realize that if you use your loan money from the refi to pay off a credit card and car, all you're doing is exchanging two debt payments for one...and making no progress.You don't use loan money to pay off loans, you use profit and/or cash flow to pay them off.You use loan money to invest with...and to use the money (profit and/or CF) from that investment to pay off the personal debt.