Use HELOC to pay cash, or use as downpayment?

[Todd Mobley]

We should have close to six figures of cash in the form of a HELOC soon. A friend and owner of a handful of multi family properties said the best use of the money is to come into a deal by offering cash, rehabbing the place, increasing the value then get a line of credit on the new property to replace the original HELOC (our primary residence), then use the new additional LOC to purchase the next, and so on.

I understand cash has the most buying power, but is that a better strategy than doing a conventional loan with a 20-25% downpayment?

$100K cash could buy 1 small multi family paying cash, or it could buy a larger 500k property using convention loan, no?

Just trying to understand the logic for each strategy.