Some mortgages charge an arrangement fee, which covers their setting up costs. These will vary according to the lender and the product you choose. The fee will vary between £100 and £400 and can be added to your loan. Some lenders will ask for it upfront and others may be willing to waive it to get your business. Fees will usually be charged for a particularly competitive interest rate, so you should weigh up the cost of the fee with the amount you will save during your introductory period.