I have had the best luck with local community banks and credit unions. Even some national credit unions and banks may do them. Navy Federal, is an example. Signature FCU says they work nationwide, or perhaps Spring EQ.
just spoke to the local bank regarding this exact option. they did offer it but there was a stark difference in rates compared to a heloc on our primary residence. 5.5 for primary, close to 11% plus added fees for the investment property heloc
@Ariel Valenzuela some local banks and CU will, depending who your current loan is with try reaching out to them. As it is a lot easier for 1st position to have a 2nd as well. This also can go back to when getting financing on a deal sometimes the cheapest rate may not be the best long term plan if you can't pull equity out with the same lender.
Even on a primary, I was on the phone with PenFed today. Rates for 700 FICO 30 year VA was 5.75 and HELOC was double that rate, in the 11% range. I would expect investment HELOCs to be higher than that.