I can't offer too much help because I don't know your area, but if you've done a solid market survey of surrounding properties and your numbers are in line with them, it could work just fine. Biggest thing that jumps out is how your payroll is zero? Is your management company one that does off-site management with no office hours? I looked at a few of those for a 32 unit but went with other options. If they are using that kind of setup, are they charging leasing fees as well? Those can add up quick.
Are you projecting any rent increase? Is the property full all the time, as well as the neighboring properties? If so then the 8% vacancy is probably ok (assuming you're lumping bad debt, loss to lease, etc in the 8%).
On the sub metering, have you looked at using a RUBS? There are additional costs associated with billing utilities back to residents that way, but you wouldn't have any cap ex to re-wire the place.
I am jealous of your $225/door insurance!! I'm paying $400/door but we have hail here.