Some of us don't have parents who have more money than we do.

Neither do all of my friends. All that's required is having parents that want to help you get a house.

For instance my girlfriend makes twice the money her parents ever did. She still couldn't have afforded the full down payment on her house without a 4% loan from her mother as they were entering retirement. This arrangement ends up being beneficial to all parties.

I wonder how common even that much help is. That would be completely unthinkable to anyone in my circle. I personally send about $400 per month on average to help my mother make ends meet. I'm certainly not going to be getting a several thousand dollar loan from anyone in my family.

For reference, this is in southern New Jersey and I'm on the older end of the millennials.

Might depend on your age group. If you were (un)lucky enough to be of home buying age during the 2005ish period, you could get a "NINJA" (No Income? No Job? Approved!) loan. This let you sneak around PMI and even having a down payment by using a 80% LTV conventional 1st mortgage, and a HELOC acting as 2nd mortgage based in order to reach full purchase price. Add in a 10 year interest only period, and you're good to go. What could go wrong?!

Speculation or saving for retirement.