The lot is surrounded by two shopping centers that were built within the last five years and sits on the corner of a major highway.

@James Klafehn The post office around us is trying to get complexes to consolidate to central mail centers, and have been paying for and installing these for complexes, may be worth a call. 

If you have a place  to park a car on your rental property, then you may be able to tap a new profit center - car rentals.

Center Dr.

One LLC per relationship is usually fine.If you define "property" in the context of this question as apartment complexes, shopping centers, office buildings, etc...you'll put each one in into its own sole-purpose entity such as an LLC.

I work in a call center and every now and then you get the 90 year old vet who didn't understand the notice and is just looking for someone to talk to.

We recently got a great place to ourselves in Center City, Philadelphia for $60/night.

I expect they are the usual uses permitted in a residential area: child care center, clubs/lodge, community care center, library, religious assembly.

He will work with manufacturer directly etc and make your life easier.Also, the units they get....materials in general....at the wholesale distribution centers are superior to what you get at big box, consumer retail stores.  

If you're using direct mail to generate lead traffic and directing them to call you or your call center, you ought to have lead sheets or scripted forms to collect calls and vet the committed from the curious.