Property Managegers: Quibble over maintenance override

[Andrew S.]

I'm in a debate with my PM over the following scenario and I'm looking for some opinions.

Tenants move out and property requires $500 in repairs (beyond wear and tear).  PM has the work done and charges $500 against the tenant's security deposit.  Tenant is fine with that.  THEN, PM charges a 10% "maintenance override" for the work to my account. I'm NOT fine with that.

My position is that the override is part of the cost incurred by the tenant and should have been added to the amount taken out of the security deposit, not charged to me directly.  The PM disagrees, citing some nebulous accounting rule that such costs are considered rental income and therefor are subject to the regular maintenance override (so far, he hasn't provided any documentation to back up his position). 

This seems crazy to me on several levels but particularly because it actually lets the PM double-dip on fees.  First he gets a maintenance override (which is fine with me, except I think should be charged to the tenant, not to me), and by calling it "rent" he also get's to collect his 8.5% management fee.

Am I missing something?