By far the best way to scale if you don't have a lot of cash is to house hack.

It's not likely your friend was saying that you would get another HELOC to go in 2nd position (banks don't like to do a HELOC behind another HELOC).My guess is he's saying you get another HELOC with a larger available balance, and use that HELOC to payoff whatever is remaining on your existing HELOC.

I want to buy a duplex when I enter college and house hack the other half.

I did a YouTube video about how I found, negotiated, underwrote, and bought this house here @RobDoesREI: https://youtu.be/PR3kYZVA3oI?

If you stay in California, I'd recommend a house-hack of some type.

I wouldn’t lend more than 65% on a new loan, or pay more than 65% LTV for an existing loan, and the 65% is if every things prefect.  

The blonde (there's a reason I mention that :-) young lady said,"oh it has been great, but I hate to inform you that you have ants in your cute little house"I was shocked, I had never had any bug problem, let alone ants......

If you want a small-multi look for a larger house with a guest house (or ADU has they call them in California) and then try to rent it to an extended family. warmest, Susan 

If you don't want a house look in Cagan's Crossing, there's some nice condos and townhouses in there. 

NO receipts to copy or review because all receipts are consolidated onto a spreadsheet by house with a description for each purchase.