I think the first place made the biggest impact.

For example, if rates go up significantly, a mortgage company might reject you based on the impact on your debt to income ratio or based on the DSCR of the company. 

That may impact quoting (you may hear that they cant quote until the carriers open up again). 

Both were hugely impactful for me and my real estate growth over the last couple of years. 

And it will impact both traditional mortgages and other lines of credit, like a HELOC.

Some lenders are going out of business, Fed rate hikes could impact their pricing moreso than conventional/MBS priced products.  

The HELOC will impact your total indebtedness and your debt-to-income ratio.

The troubles in the stock market that impact my retirement accounts so far this year haven't been fun, but they certainly have not been devastating because my real estate is acting as a counterbalance.

The advice I have received is life changing and will impact me forever. 

While I am not a credit analyst or a banker, I do not think utilizing the HELOC would impact your credit score - you said, "killing your credit".