Payment is in your bank by the 1st or they can’t stay.

I have heard of some podcasts saying “the bank wouldn’t give me a loan so my parents took out the loan.”

Should I have all expenses and income in one bank account?

However, I believe in most states if you can locate his bank account that there's an avenue. 

As I think though the Math...If a property that is worth 5.3 million today at 6% cap approximately, at 5% interest rate; if the same property I could get at 4.3 millions in 2 years if the market falls, then interest rate possible at 6-7%, my cash on cash may be better but still not significantly better due to the higher interest rate, plus opportunity costs of sitting on capital for 2 years (1.3 million investment earning 1% bank interest instead of 7% COC if invested, loss of tax break depreciation, total loss may equal 200k loss in profit), plus increase in the rents and some value add could increase the cap from current 6 to 6.7 or so.

It's not out long enough for a bank or credit union to see return. 

They will take a percentage of anything they collect and there's no guarantee they will collect anything.An attorney may be able to assist you with collection action via wage garnishment or bank account garnishment.

Also, If I am house hacking do I still need to have a separate bank account?

@Melanie HeigesOkay. that makes sense.You have a few choices for flips:your own cash, or cash pooled with other investors.hard money or similar private lenders.You don't typically get a traditional bank loan for flips due to the condition.So, you would either get hard money loans that will lend for distressed properties or use you own cash.Hard money lenders base their lending on the project, not on your personal finances.

What you will run into more though is that the bank/lender will tell you "no", because it is in their rules, not Fannie's.