Put some unexpected repairs into your budget and get as much information from the existing tenants and the home inspector.

@Supada L.Yes, burdensome unexpected costs are part of REI, but I'm curious about the inspection reports dating from last year that you mentioned. 

If something unexpected comes up during the purchase a good agent could give you some valuable guidance.

I had some contractor issues and unexpected repairs that took us longer to complete.

Apart from unexpected reno costs, carrying costs, closing costs, etc.

Should an unexpected financial issue arise, guess who will be at the bottom of the list to pay that month. . .good ol' cousin Ryan.

@Scott Pollock it's actually within FHA acceptable guidelines to have a 2nd fha loan if your situation has changed unexpectedly as long as the new subject property is 100 miles away from your current fha primary home.

In addition, investigate how much you can really rent the other units for by looking up comparable rents in the area.Bonus Tip:Always save at least 1-3% of the value of your home for unexpected expenses, even if you're house hacking.

We have a young family and don't want to get in over our heads on debt should something go south (and don't want to be over leveraged if we decide to move to a new primary)40% was where we felt good about the cash flow, and can be relatively sure we wont be losing money each month even if something unexpected goes wrong, and we have it sitting in the bank from a stock sell off.

With these extra items however, we feel that 50% fairly captures their unexpected nature while still allowing for our rehab plans to be possible" or similar.