Now I am in the process of fixing the two units to get them rent ready and taking care of deferred maintenance on the other two.  

So for these, you just need to work out how much less than ARV you care to go.But if you're talking commercial (5+ units), then yes, rent is very important in helping determine value, because their market value is heavily influenced by the market cap rate there!

Based on feedback from other hosts I will probably add a TV in the living room and portable air conditioning in the bedroom this Spring.I am very careful not to allow long stays because I want families that are vacationing -- not homeless people who seek to establish residency. 

Anyone out there who has taken a DIY approach to REI (ie not through turnkey companies) and is actively investing in 3 or more markets (meaning not just holding rentals from once upon a time but still looking and buying in at least 3) care to chime in?

Took care of the landscapping myself rather ham hiring it out.3.

The rules have changed over the years and you have to be sooo careful nowadays.

Build a nice landing page to send traffic to the landing page and track carefully.

I assume that he travels and doesn't care to pay full-price for an apartment, considering he will be traveling a lot and he is here on business.

Analyze carefully and feel free to tag me with any other questions on this. 

Other holding costs include insurance, utilities, and lawn care.