Hi Steve,
You can obtain or refinance a house mortgage without having a HELOC or even considering a HELOC. The big difference is that a mortgage is a defined loan, paid out by the bank in one lump sum, that has defined repayment terms. A HELOC is an adjustable interest rate line of credit that you can tap into if you want, or just leave it there - if you don't touch it, it doesn't cost you anything (typically, some companies charge a fee to maintain it). Also, the main mortgage is collateralized by your home and takes first priority in the case of default - a HELOC is also collateralized by your home, but generally gets secondary treatment in the event of default (hence a lot of lenders pulling them these days). I've personally found that having a HELOC is a great way to 'insure' your mortgage without having to consider other expensive insurance plans (like those plans that will make your mortgage payments if you become unemployed). It's basically a checkbook that allows you to draw, at your will, anything up to your HELOC limit. Depending on who underwrites the HELOC, the same lender who did your mortgage, or a separate lender, can affect how easy it is to obtain and keep. Many mortgage lenders see a HELOC as a 'safety net' for borrowers because they know a borrower will draw on the HELOC before defaulting on a loan. If the HELOC lender isn't the one that lent on your main mortgage, the situation is reversed - they know that if you're about to default, you're likely to draw down the HELOC to pay your primary mortgage. If the house goes into foreclosure, the HELOC lender will more than likely end up with nothing in that situation.
EVERYONE should obtain a copy of their credit report and score at least annually! You'd be amazed at how little things can DRASTICALLY change your credit score. These days, you need a really good score (750+) to get a loan with the best terms, and you need a much more 'acceptable' (650+) score to get any kind of loan at all compared to just a few months ago. There was a time when a 650 score was really good - now that score can cost you a lot of money in higher rates and/or points.
The best time to get your credit in order is when you don't think you have to... $hit happens in life...
Martin