Quick Bookkeeping question

[Nick Causa]

Received our first rent check. Feels good. I have certain amounts that i want to divy up to go towards future expenses (capex etc). We also set up a competely separate account for the house. Do we leave that excess in the account after paying the mortgage? So if rent is $1500, the mortgage is $800, and all future expenses (capex, vacancy, maintnance) are $500 (these arent real numbers im just making them up) do we just keep leaving $500 every month in the account until we need it?