Cash Reserves for a House Hack

[Connor Duff]

I'm currently reading up on house hacking and how to analyze deals. I've read from multiple sources that you should save apart of your monthly cashflow for reserves in case of vacancies, repairs, emergencies, etc. My question... is it necessary to set aside money every month from your cashflow before taking a profit OR can you simply set aside a set amount of money at the very beginning when you buy the deal? Or is either approach fine? For example, let's say I want to invest in a $400,000 property and I have $24,000 saved up to invest. If my down payment is $14,000 (3.5% FHA loan) then what if I just put $10,000 aside in cash reserves from the get-go? Thanks!