Assuming that you're in the United States, I can share my HELOC experiences/anecdotes. I've opened HELOCs on two different primary residences, once with a big bank and another with a credit union. In both cases, the financial institution was interested primarily in two items:
- The combined loan to value (CLTV) of my property after opening the HELOC - the bank/credit union effective would have a secured loan (effectively a lien) on my property in the event I did not pay it off. Having a lower CLTV offers lower risk, in the event that property values dip - I was fortunate that my CLTV ratios were under 0.8 (80%) both times.
- My personal income - this was used to measure my ability to repay without resorting to collecting via lien (longer and more expensive process)
With these two pieces of information, I was only asked a cursory question regarding purpose of having the HELOC - at the time, I was planning on using each HELOC for emergency source of funds and possible home improvements.
For each HELOC, I was given a set of checks that I could use to withdraw money from my line - no further questions were asked when I used the funds during the draw period.
YMMV, each institution will have its own underwriting rules.