House hacking a duplex, even with negative cash flow upfront, is a great way to build equity while learning hands-on.

In long run could have some negative consequencesalso Is it just residential or commercial as well?    

The possible negatives of subject to have been thoroughly discussed.  

Instead of jumping into an expensive Long Island market with negative cash flow, consider investing in a Texas market like San Antonio, Houston, or DFW suburbs—these areas offer strong rental demand, lower property taxes than NY, and better cash flow potential.

When including maintenance/cap ex, vacancy, pm, misc he will have little, and possibly negative, cash flow.if he invested almost $250k to add less than $150k of value (assume some of the current value came from the home appreciation), there is no cash flow until the initial negative equity position is recovered.  

At $1200 in rent, you will probably have negative cash flow. 

I use a point system for screening; applicants get positive points for positive aspects, lose points for negative aspects, and I have a point threshold for each property. 

If you're willing and able, I do recommend the "house hacking" strategy which is just a fancy name for buying a rental property and living in one of the units, because you'll get very favorable financing - an owner-occupied fixed-rate 30-year mortgage.I'd also say, analyze that property as if you won't live there and it's a pure rental, and make sure the property is still cash flow positive if there's a tenant in your unit because then you'll know if it's actually a good investment.And when you analyze it, include payment of a property manager in your #s because if you don't, and doing so would make it go cash flow negative, then you've just bought yourself a job because you literally can't step away from managing it without losing money.

In some cases, after running the numbers, I’ve even faced potential negative returns, causing me to miss out on promising deals here in South Florida.That brings me to my question: I currently own two homes—one is my primary residence, and the other is a rental property.

Is $150 negative cashflow a lot for you?