So should I use up a good chunk of heloc and minimize the hml cost.  

There are so many different factors that can affect the tax liability of the property, (especially as you develop a portfolio) and it's very easy to claim it as a loss if you have a good CPA.

If you loan today, at highs, then the market drops, then you repay at depressed prices, you’ve protected your portfolio from a loss while selling high, buying low, and adding a rental to the portfolio 🙂.

I had minimal experience with all of them.

They aren't so worried about running in the red (homeowners simply pay the mortgage from their monthly income and don't call it a loss).

Lots of online training and is well worth the minimal cost. 

House Hacking is a great way to minimize expenses, obtain property for very low money down, and learn the ins and outs of property management.

Both of these loans will normally require 20% down.If you are concerned about your primary rates, you could use an FHA loan to purchase with minimal down, live in the new property for 12 months, then refinance it or rent it out. 

If I’m buying properties for long term buy and hold, and am buying quality properties with minimal/no rehab, and with little/no cashflow (buying for long term loan pay down, equity, and tax benefits), is it hard to get multiple mortgages?

ADUs where there are minimal comps and obviously an ADU are sometimes far below the hands of cost.