What percentage of rent are you using for reserves?

[Trevor Cox]

When I first started looking into real estate investing a few years ago, I read multiple sources that said a conservative number for repairs, cap ex, vacancy are each 10% of rent. I've been seeing some people using numbers way lower than this (5% and even lower than that sometimes). What percentages are you comfortable with from a conservative position? I know these numbers greatly depend on the age and condition of the property.