smith manoeuvre

• manulife one
• scotiabank step
• td flexline
• national bank has one too
• bmo readiline

the big advantage is that you can pre-pay with excess money to pay down the principal sooner,
but also that turns into HELOC room, which you can withdraw immediately and then invest
and then you get a tax deduction for the interest paid on the heloc because you used it for investment

pre-paying the principal sooner also decreases the amortization, and thus the total interest paid over time