The line of credit amount is available to the borrower and no interest is due until some or all the money is used. When the money is paid back, the line of credit is again available in full to the borrower.
The specifics of the repayment will depend on the HELOC lender. It may require interest only or it may require amortized payments of principal and interest.
The proceeds from a HELOC can be used to make improvements on the home or anything else such as medical expenses, college tuition or unexpected expenses or other liquidity issues.
Unlike personal credit card interest, the interest on a HELOC may be tax deductible. Your tax advisor will be able to let you know about your situation.
Rates and fees can vary widely on HELOC loans. Borrowers should shop around, compare and get recommendations before deciding on a lender.