But it's also tough to raise rents & keep tenants if they are paying excessive heating costs. 

The level just before the market dries up and you outprice the renters. 

I have 1 rental and normally ask for first month rent ($830) plus a deposit ($500).seems like renters just move out after the lease is over and treat the deposit as part of their last months rent.... so i end up with actually no deposit so no leverage for excessive wear/damages.

Then if you don't get it the excess funds would go to lower lien holders then the foreclosed former owner like any other one.

This shows that you do not excessively use your available revolving credit and that you have a buffer to absorb emergency spending.

As to using an agent, seems pretty cut and dry, unless you want to pay more in commissions.......???

After receiving this initial interest, the calls have since dried up, and I am considering Zillow as my next marketing avenue.

You will not lose holding costs due to contractor delays, inspections, finding those 'easter eggs' that come up when you pull down dry wall.If you can get it there are still FHA mortgages with 3.5% down for owner occupied. 

If you do not use all the excess funds you will have BOOT and be taxed on it.

I was under the impression there had been a disturbance, some excessive noise and some yelling.