It depends on the price point but generally, enough to cover the worst thing that could reasonably happen which is usually going to be a roof replacement, but as number of units increases this can be stretched a little bit as it is unlikely you will have 5 roofs go out at the same time. (exception hail storms; but hopefully you have insurance for that)
@Khari Lewis It's generally good to have ~6-8 months of mortgage payment in cash reserve for each property. Though this will vary depending on the number of properties you own, financial position, condition of the homes etc. But 6-8 months of debt service payments is a good marker to work from.
Agree with @Aaron K. on the most expensive repair you could face soonest. So you're in FL. I'd say roof and ac might be the biggest threats. How old are these items? You should have an idea of remaining life from your inspection while in escrow. If the roof was replaced a year before you bought the place, and the ac is 18 years old, I'd budget for new ac (which is my benchmark in AZ).
Regardless, I would highly discourage underfunding reserves and lean towards having more than you'll probably need. I did not survive an underfunded situation in my early 20's with 3 rental properties and had to liquidate all 3 of them at losses. It was a demoralizing ugly situation that set me back years. Do not make the same mistake! Make sure you have the staying power in reserves to weather challenges.
Hi, I am relatively new to being a landlord. My recently filled rental does not have a mortgage and I am using 10k as a nice round number to keep in reserve. A new roof is about 5k, a complete new AC is about 5K. Both of these items are less than 6 months old (Thank you Hurricane Michael) in the house I am talking about but 10k is still my comfort number. With 10k in reserve there is zero stress in worrying about capex.
I keep 3 months of gross scheduled rents, which is roughly equivalent to the 6 mos. expenses that others mention above. Moving forward, I add about 3% GSR each month. Aside from the need for the reserves, as @Taylor Chiu mentions this will be required by your lenders as you get more mortgages.