@Ryan Rowe, I like the approach which is a blend of the information @Scott Trench provided above, and the "it depends" answer posted by @Chris LumLee.  

3)  Does the personality of this agent blend with yours?  

Plus from our experience, they pay a lot more attention to the property, are easy to get a hold of, can provide quick and seamless legal advice, help keep contractors honest, and quickly help you handle any issues that arise.

I'm looking specifically for one that is not too complex, can be scaled and help us scale easily as we grow, and also integrates seamlessly with Carrot.

You can also try reaching out to local property managers to see if they have any units nearby to give you an estimate of what you might get for your units.Use the above in combination with a blend of data from Zillow and/or Redfin and you should be pretty close!

There are many ways to manage properties electronically these days that provide for a seamless and secure experience. 

Again, it could be multiple.Then make a spreadsheet that is a blend of the two...some events pan out, and some do not.Then you can look at the optimistic items and figure out what kind of marketing strategy (acquisition), or retention plans (repeat guests) needs to be in place to help make those optimistic scenarios happen and maybe give your gut more information to go one.Hope that helps.Mike

They sweep the money into the account weekly and it's seamless. 

Must blend with the neighborhood and vegetation. 

And, how seamless can you make the transacton for the seller - can you close in 30 days or less, etc.?