I plan to do my own background, credit and eviction check. 

A mentor of mine with 400 units had said I can use a large seller credit to cover most of the down payment on a property I'm looking at.

Since Covid, Wells Fargo stopped opening new lines of credit, and from the info I gathering will completely be getting out of the HELOC business.

Keep in mind that each lender may have specific requirements based on your credit, income, and other factors, so you’ll want to check with them directly.I don’t do conventionals but I’d recommend reaching out to Brandon Croucier with All Loans Funding on here for those he’s really great. 

Given your strong net worth and experience, investors might be interested in a short-term investment with a clear exit strategy.Home Equity Line of Credit (HELOC): If you have significant equity in your personal residence or other properties, a HELOC can provide access to funds without selling any assets.Securities-Backed Line of Credit (SBLOC): If you have an investment portfolio, you could borrow against the value of your securities without liquidating them.Seller Financing: Negotiating with the seller to finance part of the purchase price can reduce the immediate cash requirement.

DSCR loans are based off of down payment, credit score and either actual or market rents so it helps to supercharge an investor's real estate goals and net worth.

Instead, Sreit has relied on its line of credit.

What documents do they require, what credit scores do they allow, how do they verify previous rental history, etc.?

I’m based in the NY/NJ area, and I’m exploring a few different options:1.Bank Loan – I know banks usually require steady income to approve a mortgage, but would a large down payment (maybe 20-30%) and good credit be enough to get approved?

This is a local credit union, this would only be an option for an investor that both owns the properties near Austin, Texas, and that personally lives in the area as well.