Keep you cash on the sidelines in case unexpected expenses occur. i.e rehab goes over budget, appraisal comes in low...

we weren't aware of that and got slapped with a huge tax fee unexpectedly!

For me, everytime I think my life is on a straight road next thing I know here comes an unexpected twist and turn.

Things don't always go as planned so plan for the unexpected.

I understand unexpected things come up as the work progresses, but how is this typically handled?

Heaven forbid something unexpected happens. 

Make sure the $400-$500/month cash flow is enough to cover unexpected costs.It wouldn't hurt to look for other refi options or consider a different loan option, which might offer better terms.

We deal with some of the best "we buy" folks on the east coast.When the property condition is unexpected, they terminate during the study period... as they have reserved the right to do. 

That's significant growth.However, consider these points:Make sure you have reserves for unexpected repairs or vacancies across all properties - THIS IS KEYRun the numbers carefully on the potential house hack and multi-family to ensure they make financial sense.Consider the long-term strategy: Will the potential appreciation and equity build-up in the new properties outweigh the increased costs on the Farmington condo?

. $45k from several unexpected large repairs (water leaks, roof collapse, siding rot, plumbing main line, etc.)These issues are also causing me to rethink the assumptions in my model, increasing my vacancy rate from 8% to 12%, repairs from 5% to 20%, and capex from 5% to 20%.