Often the percentage will lower if you have multiple properties, so ask them if that's the case if you are thinking of doing more investing in this area- Maintenance costs | ask for an hourly rate for general maintenance, any routine maintenance that you should be aware of, and if they have an in-house maintenance team or if they use third party maintenance.

Another bonus: A few months ago, I implemented the Miracle Morning routine and I’ve NEVER BEEN MORE SATISFIED AND PRODUCTIVE.

Routine maintenance and capex are part of the business, but tenants should be responsible for reasonable upkeep and to not break items. 

(She routinely does this and has purchased hundreds of properties.)

Simple things like faucet repairs, routine plumbing, electrical outlets, and other things of that nature are maintenance. 

In the Central Valley, the summer temps routinely climb into the triple digits. 

I know they can handle the routine maintenance and rental collection but have thought about property management. 

Also, we routinely overpaid on the principal because we weren't thinking of doing anything else with our money at the time, and before we decided to house hack, we made a sizable principal payment in order to get a larger HELOC to use for investing purposes. 

I don't want to sound cynical, but I know of ownerswho charge less on the late fee (in your example, say, $25 - $35)and then expect to collect it in many cases.Set it too high, and people will really try to pay on time.Set it just right, and people will routinely pay late, andyou collect the fees.

Others are irregular, but frequent - routine maintenance, snow removal, mowing.If you're looking at a 24 unit apartment building, 50% of rent is a pretty widely used number.