But I've come to know Marcus and will gamble he won't mind, and this story lends itself to how hard it is to vet a person you might want to hire.

To me, it is speculation or gambling.

Quality of service and pricing definitely do not correlate, as many of the higher-priced custodians have some of the least responsive customer support.With checkbook plans, the role of the custodian is minimized and you may find a very low flat-fee for the custodial administrative services- usually not on the custodian's web site, but by private arrangement with the advisory firms like mine that offer the legal and consulting side of the service. 

Or do most people just find listings on the web?

Do you guys have any recommendations on website resources where I can see if a neighborhood is doing well or not, if it has high crime rate or it is about to turn into a ghetto? Or maybe see the income of the majority...

You will tend to find that, absent oil or gambling money, states with higher income taxes end up with lower property taxes, and states with lower income taxes end up with higher property taxes. 

Some owners instead of gambling on the premium  that’s possible with individual leases just lease out the whole 4 bedroom unit at a slight price break. 

If this link doesn't work for you, do a web search on Brandon Turner and document title shared above.  

The web sites are almost exact copies. 

Riff Raff, whiskey, gambling, prostitutes, con artists, and other shady characters run gamut when the refinery is doing major work.