Purchase in Hudson County NJ

[EDWARD M.]

I just came home from visiting a 3-family home selling for $569000 with property taxes of approximately $10,300. Basement 2 bedroom receiving rent of $800 (can rent for $1000-1100 easily), first floor 3 bedroom current owner lives in, second floor including partial attic 3 bedrooms renting for $1500 (can rent for $1650-$1700, same for first floor apartment). Apartments are in great condition, move in ready. Basement and 2nd floor tenants will stay, they have been there for several years. Water is included in the rent payment for both tenants. However, the basement tenant is single no others living in the apartment, second floor only two people living there. Has off-street parking for at least 6 cars, can probably increase rent for another $75 a month each. 

I'm calculating a monthly payment of approximately $3,931 going FHA, and $3,186 going conventional with 20% down. I'm not sure how I should analyze this and if it's a worth while purchase. I will be living in there for at least 2 years and moving on to another hopefully by then if the market works in our favor. This area has a VERY low vacancy rate and I feel comfortable making our first purchase here.

Does it make a difference in analyzing whether I go FHA or 20% conventional? Obviously monthly payments are much less going conventional but how do I determine if the return is favorable? I need help, we did love the house since it's in such great shape.