@Samuel Cardenas I used a HELOC to do a cash purchase on a duplex that I am now renovating and plan to rent out. After renovations are complete, I plan to refi the property to pull my cash out to pay off the HELOC and the renovation costs.
The HELOC I am using has a variable rate that could change quarterly. So, I don't mind using it for a short term project, but would be reluctant to tie it up for longer than a year due to the interest rate uncertainty (Although the Fed Reserve Chairman recently mentioned that they are not planning on raising interest rates anymore this year). So far, I have only experienced one interest rate bump that I factored into my estimation when planning the deal.
The HELOC was very easy for me to use as it was setup as an account with my credit union and I could withdraw funds whenever I wanted for any amount up to the limit. I found it to be useful in negotiating the deal and the time to close is greatly decreased when you do not include financing in the deal.