Can’t say I’m surprised, but what are their alternatives?

However, alternating back and forth between the two solvent carriers is your issue. 

Alternatively, If your numbers are accurate, there is definitely enough spread to work with a HML if you are employed, have decent credit and can put some skin in the game (ie 10% of the purchase or so).

If you need alternatives then try posting in the New Jersey forum. 

Another alternative for the construction loan to the local banks is US bank. 

I ask this, for it to be an alternate to getting a partner or saving more to cover 100% of a downpayment. 

Is there a better way to explain this to the underwriter or am I better off looking for an alternative to HELOC financing?

What are some alternatives for free seminars that can teach me about real estate?

Alternatively, you could sell after the 2 year mark and take that capital and buy a house hack: a 2-4 unit property, live in one unit and rent out the others.  

A lot of your peers starting out will try and force buying somewhere where it doesn't work, then end up pushed out the game in a harsh manner because of failing to calculate alternative options that will set them up for long-term.