The answer lies primarily in two places. One is the cash flow and second, what you alone want out of this property.
In order to determine if this deal takes you where you want to go, first look at the money in, less money out, pay yourself first then see if there is enough left over to pay the mortgage (even if you decide to pay cash).
If there is money to compensate you for operating this 4 unit park then look deeper. Due diligence will be the next step to make certain that the property itself is what you are being presented as fact and if it can remain that way, and if it will take risk or money for you to do so.
With this info in hand you can decide if their are additional exit strategies for you to consider or pursue that may make you greater money or perhaps protect you if one or more does not pan out.