Another factor will be whether it is anchored by a well-known name, such as Wal-Mart or Lowes to give it some assurance of long-term traffic.

Further, I feel you should be anchoring all of this with a website to built trust.

You don't want to do any long term installment contract without an attorney, if you can find one to do one.The DOS and FHA regulations are anchored in federal law, not administrative "discipline" and administrative rulings carry the weight of federal law. 

I am thinking of doing some retail development myself but keeping it to smaller projects that take 6 months to 1 year to get a return back versus the larger shopping center 3 to 5 year anchor builds.  

Some have great success throwing out a number first, called anchoring.  

Maybe anchor it with "what is standard in real estate is $1000".

For the meantime, they mostly seem interested in leaving themselves financially "available" to the best job opportunities....which means not anchoring themselves with a mortgage.  

You might get the current owner to go down to the local building department and the code enforcement department if they are separate and find out exactly what he or she has to do to get the lien removed then at least you will have that much more knowledge, an anchor for a possible deal. 

All the fruits of the land, ability to profit from any parcel of land is anchored in the rights and interests that are conveyed in the property or a contract.

The end of the Busway is anchored by the Swissvale Busway, which is a park and ride access to the P1 and P3 into downtown.