Rent Hacking Plan, Help Me Evaluate

[Nicholas Graphia]

I'm looking to rent hack while I'm saving up for a down-payment on my first RE purchase. I'd like to use the money saved/earned rent hacking to invest in a triplex or fourplex. 

Here's my plan: Rent a nice 2 - 3 bedroom house in New Orleans, in a desirable neighborhood, and rent out the extra room(s) to carefully screened professional type roommates.

Hypothetical Numbers for 2 bedroom house:

Cash Outlay:
$1,500 deposit
$4,500 (3 months rent set aside as cushion in case of vacancies)
$1,500 for furniture purchase

-Find roommates through Facebook marketplace and/or personal network. I'm a single professional in my 30s
Income
Charge roommate $900/month + utility share + a security deposit. From their standpoint they get a turnkey place, and more square footage for their money compared to renting a 1 bedroom.

This would keep my monthly rent payment down to $600. My housing budget if I lived solo would be $1,200/month. So if the extra room rents 8 out of 12 months the rest of the year is a wash. But I could still rent the room to shorter term tenants if need be to keep the income stream going.

Seems simple enough, but there could be something I'm overlooking. Thoughts?