HELOC fixed rates advice needed

[Hoi L.]

First time investor, hopefully the start to long term financial independence.  

As someone starting out as long term buy-and-hold rental investor, we are looking for relatively good conditioned places in $125-300k/units.

HELOC terms: all fixed with 80% LTV for my primary residence

$160k available to take out from HELOC; also another $150k in current bank accounts

5 yr at 2.25% (~$2900/month in P&I payments)

10 yr at ~2.43%

15 yr at ~2.65%

30 yr at >3.15%

Question:

Which HELOC terms would you recommend?

Lowest APR/length with highest monthly payments or take 15 yr (30yr apr is too high in my opinion) for lowest monthly to maximize monthly cash flow to save for future additional properties?

thanks so much!