Keep us updated on what your lender says, and I’d be curious to hear if anyone else has pulled off multiple VA loans in a year successfully! 

As mentioned in a prior comment, a 401k plan does not require a financial institution custodian or trustee, unlike an IRA.The terms "plan administrator" and "plan provider" oftentimes mean different things to different people, particularly in the Solo 401k plan space.

As far as I'm aware most credit unions will only lend on properties in their area of operation so not sure it makes sense to join one in a different state.

Is your property in a Class A, B or C neighborhood?

It sounds like you're in a pretty good position with some nice options.

The only thing I would say in a area that is cheap is flip it wash your hands of it ASAP .

You have to determine if the additional complications and costs are worth the investment in a Title Holding Trust or Land Trust.  

If the only MFH options you're finding are in areas you're not comfortable with, it might be worth focusing on a duplex in a better neighborhood.Saving up for a larger property later is a valid approach too, but keep in mind that real estate tends to appreciate over time, and waiting might make it harder to enter the market later.

If they’re selling for a $400k+ gain they could look at a 1031 for:A super nice 2-4 unit they wouldn’t mind living in a unit of where the rental portion exceeds their 1031 sale. 

Northern NJ has options as well, but MTR works better in a lot of areas because there is demand.