I just completed the inspection yesterday and it seems the roof will need to be fixed(over 20 years, the boiler system is very old(there are 3 boilers), one of the 3 hot water heaters(HWH) is leaking and the 3 car garage (which is one of the main reasons the property is compelling as an investment purchase) is not structurally sound and may need to be demolished.

I'm open to working/investing in all of NJ so distance doesn't factor in too much for me if the opportunity is right. 

How the legislation and regulations are written and interpreted will be a big factor in whether it is worth your while to accept pets.Here in NB, we are allowed to discriminate and not allow pets, but other jurisdictions (ON) that appears to no longer be the case.    

Your property could become a super-fund site right along with the gas station.To me, #1 is a minor factor, if a factor at all.

BUT it seems a bit daunting to get started.The main concern I have is that the big appeal comes from the fact that there are fewer and fewer parks every year from those that are sold and converted to some other use. 

A few factors here... are you doing the work or subbing it out?

However, the mandatory (since the home is still mortgaged) insurances (windstorm / hurricane mainly) escrows adds literally another $2,000 to their monthly payment.

There may also be non-monetary factors to consider, such as the family members expected rate of appreciation for the property and tax considerations. 

I recently looked at a duplex and wanted to get some thoughts on if these items should be factored into the offer price:The water heaters were over 10 years old, both gas furnaces were over 10 years old, the water was not separately metered, the front porch (cement) had some cracks in it, and both units would need some paint and new carpeting. 

But this is only after you factor in ALL the assumed potential expenses.