Hey Ashley,
Also in Central Jersey and have been investing for a number of years now. For starters, are you sure that you would be able get a 5% rate as a first time home buyer? Not 100% sure about that but double check.
Few things to consider: It's a tough market now with interest rates, especially here. Any MFH you buy for around the 500-700 range in Central Jersey in a better town will most likely require a lot of work, so you have to take that into consideration. Most likely won't be breaking even.
Even if you do fix something up, you can't force appreciation to the degree that we've seen in the past 2-3 years. You have to be willing to play the long game and overpay with the intent that eventually after renovations you will take maximum market rent and turn a profit. A lot of this is dependent on where rates go in the next 6-12 months.
As far as your SFH strategy goes, not sure what the job market is like in South Jersey, but I know in Central Jersey there are a lot of NY commuters, so renting will always be easier. Try to look for deals, play the long game, but if the number's don't add up don't feel compelled to do anything now because you'll just feel maximum pain a year out after purchasing.