Sounds like a good situation from the employment perspective. 

You CAN limit that agreement to a specific property; but, as others have stated, agents are looking for a certain amount of loyalty from their clients.If an agent gets vibes from a prospective client that indicates that they want to cheapskate and not pay a professional for their service, they are not likely to waste their time with them.

However, it sounds like you are confused about the different types of auctions that exist on Auction.com. 

They will provide you with an overview of what needs to be done and what they will charge.

It's like the 70% rule, you can use it to narrow down 100 deals to 30 deals to dive deeper, but you need to know estimates per house..

Gas-meter-gas provider.  

They might be interested in partnering or providing funding for your project. 

A “syndication” is almost always a capital raise for the sale of a security/investment.  

I invest in land and have done entitlement/zoning and other DD work successfully for years.A broker called me this morning on a property I have on a busy interesection and has a QSR client who likes the location, but does not want to do a ground lease, only a build to suit. 

What is their previous rental history like?