I believe the most important point in your decision is figuring out your appetite for risk.

Does this 4 plex already have a full fire suppression (sprinkler) and interconnected fire alarm systems?

Lower suppressed SFR in the same zip code.

When this is combined with a work/live situation I've found they've either carefully cared for, albeit sometime with wacky taste, or have substantial deferred maintenance.CRE investors, in general, don't have an appetite for investments like those described by you and above.

My question is regarding a 3 family (former nursing home) that I am looking at that has a sprinkler system already installed with  heads all over the property and a large fire suppression system in the basement.  

Apart from that buying investment properties in NJ (Parsippany area), seems outside my risk taking appetite currently.Any ideas on buying foreclosure or pre-foreclosure properties in that area will also be helpful. 

Will they have an appetite for this type of deal?

Here are the strategies I can think of:1) Save up $30,000, buy a house, then simply save until you have $30,000 again (with the money in a savings account or stocks depending on risk appetite), then buy again, rinse, repeat, etc..2) Save up $30,000, buy a house on a 15-year fixed mortgage to get the lowest possible rate, then when you have enough combined cash and cashable equity in your property, immediately do a cash-out refi and buy another house.3) Save up $30,000, buy a house, then when you have enough combined cash and cashable equity in your property, take out a HELOC and buy another house. 

The rent rates are a little suppressed in comparison to Sumner County. 

It all depends on your risk appetite and investment strategy.