I use a combination of "rollover" rental income (basically taking any net income and plowing back into the next purchase, snowballing maybe?)

This is the function of an agent.

About a week later, call whatever number USA.com shows or use online tax/property records combined with the almighty Google to find a number for the homeowner if you can.Two (possible) touches in a week puts it in a motivated seller's mind that you're serious.

We also do annual inspections before we renew leases, and we let out tenants know that this is to make sure everything in the house is safe and functioning like it should.

Again hit the search function. 

@Brennan Utt Hi Brennan.I agree with @Jonathan Key The bath in your picture looks functional and it is a good feature to have a separate shower and tub in a wash room.  

cap rates are just a function of NOI / purchase price right?  

You basically have three options (or some combination thereof):1. 

The NSF fee and late fees were paid promptly but the tenant has needed more attention than my other 5 units combined.  

When I say nice, I don't necessarily mean expensive, or content rich, but something that is aesthetically pleasing and functional, and remember lots of branding.