Every strategy on this site runs on a line of credit, which means every strategy on this site starts in a lender's underwriting department. Before you plan your first chunk, it helps to know what they'll look at when you ask for the line.
For a HELOC, four things carry most of the weight. First, equity. Lenders commonly let your total mortgage debt run up to somewhere around 80% to 85% of the home's value, so the room between your current mortgage and that ceiling is your maximum line. Second, credit score. The line is cheapest and largest for scores in the good-to-excellent range, and below the mid-600s the offers thin out fast. Third, debt-to-income ratio, your monthly obligations against your monthly gross. Fourth, proof of income, pay stubs and W-2s for employees, and usually two years of tax returns if you're self-employed. Some lenders want a full appraisal, others use automated valuations, that part varies.
If an application is a few months away, you can improve your hand. Pull your credit reports and dispute anything wrong, errors are common and they cost real money here. Pay card balances down before the statement dates, since utilization moves your score quickly in both directions. And hold off on other new credit, because each hard inquiry chips a few points at exactly the wrong time.
The approval isn't permanent. A HELOC contract lets the lender reduce or freeze the line if your home's value falls or your finances deteriorate, which we covered in Who Can Close the Line Your Strategy Runs On? A strategy that assumes the line will always be there is missing its backup plan.
One more thing before you sign anything: shop at least three lenders, including a credit union or two, because margins and fees on HELOCs vary more than people expect. Then size the line for the job you're giving it, which we walked through in How Big Should Your Line of Credit Actually Be? Approval is the easy part to get wrong by rushing. The how it works page shows where the line fits once you have it.