They are also offering a co-signor. 

Experts here might be able to analyze our situation better and giving this a shot.We started our REI journey in Jan 2019 - Purchased a 1B1B condo in a co-op in NJ with a fully furnished basement and renovated floors, kitchen and appliances with smart switches throughout the unit ($63K as 20% down for a 15yr mortgage at 4.25% fixed rate).

You  may still need a co-signer...

Essentially, your joint venture ("JV") Partner will likely need to qualify as a co-borrower and co-guarantor (if you are buying the property in your own names and will have your individual names on the deed).

I have the opportunity to buy a home that a co-worker has. 

Of course there are certain exceptions, but we do need proof of their ability to pay, whether it's savings/retirement or a co-signer.

However, under FHA loan guidelines you can purchase another home with an FHA loan in the following circumstances:You’re relocating due to a new job opportunity.Your new home is more than 100 miles from your current FHA-financed home.You need a bigger home to provide for a growing family.You’re getting a divorce and your spouse is staying in the current home.You were a co-borrower for someone else’s FHA loan and want to buy your own home.You’re not using FHA loans to build an investment portfolio.You’re buying a HUD real-estate owned (REO) property.You’ll need to prove your current home has at least 25% equity to be eligible for a second FHA loan for an increase in your family size.

I have the opportunity to buy a home that a co-worker has.

If you're intent on purchasing now though, you'll likely need to either find a co-signer or a hard money lender willing to take a bit more risk (although that could be more expensive).

Hey @Lloyd Spencer:I'm not sure how Jersey City would treat it from a CO standpoint, but I would also consider what the state requirement will be for the next Green Card inspection through the NJ DCA.