Lenders will look at several criteria:
Your credit history and credit score.
Value of the property you want to remortgage.
How much equity you own.
What you want to borrow against the property value (i.e. the Loan to Value).
You will often be asked to sign a contract via a solicitor confirming that the remortgage proceeds will be used to repay the debts in full.
In some cases, you might have an excellent interest rate in your mortgage and are reluctant to remortgage and lose those cheaper rates. If that applies, you can consider alternatives such as a second charge loan.