I had a huge remodel, and when I finished I sat down with the customer to go over the job.

I am calling off a custom list.

I would check into Padsplit if your really interested in this type of approach.

As far as automating as much as possible and treating the properties as a professional business, is using custom email address for each unit (like: 123StreetA at company dot com*) taking it too far?

You can vet them here by checking out the references on their profile page and actually talk directly to folks who have worked with them. 

Check out the Events tab at the top to find local and virtual meet ups.

You can also check meetup.com or search facebook for real estate investment groups, clubs, or meetings in your area.Ask questions!

Check out Meetup.com, or search here on BP for networking groups in your area. 

My wife and I are considering buying a plot of land and either building a custom build on it or putting a manufactured or modular home on it. 

also, get clear on your expectations with your agents, find out exactly what they're doing weekly and what they want you to do weekly, and stay in touch every week. check in every monday.