Best way to reserve for repairs

[Dawn Anastasi]

I have thought about 3 strategies for putting money aside for repairs on a rental property:

Method A - Determine an amount and "escrow" that
Example: $2,000 (depends on size of property)
Put away $166.67 until that amount is reached, and if repairs are needed, take from that reserve and pay it back until reached

Method B - The 10% rule
If rent is $800, put away $80/month for repairs

Method C - Budgeting repair costs
Example: furnace is $2300 and will need to be replaced in 10 years, so budget $19.17 for that, roof is $6000 and needs to be replaced in 15 years so budget $33.33 per month for that, etc.

Method A is top-heavy, but I feel it works better to make you more prepared sooner rather than later. Method B seems low to me. Method C is more "actual" but how can you predict what costs for something will really be in 10 or 15 years?

So far I've been using Method A, and have never been caught with my pants down (even after needing to replace both a furnace and central air unit which are two big expenses) but I have an open mind for other ideas.