I am not a legal professional. I do have some experience of claiming in a distance selling situation. My understanding of Consumer Protection (Distance Selling) Regulations 2000 is that they would take precedence in your circumstances. The supplier/contractor's offer of some form of gttee must not deprive you of your basic rights. It is important that you let them know in writing (an Email will do but make sure you have a copy with the date and time on it) that you have cancelled the sale. (I would say in it simply that you have found the product unsatisfactory and you understand that you have a right to cancel the sale; that you are doing so by means of this Email and wish to have clarification of their returns policy as soon as possible). You must have done this within the cooling off period if they have given you the required "information before contract" which means telling you your rights before you commit to purchase. This info must include your cancellation rights, if you haven't been alerted to your rights, the cooling off period is extended.. Forget their Peace of Mind nonsense. Google and read the DSR 2000 Regs one step at a time. Most will not apply to your particular case but Regulations 7, 10 and 11 cover the main aspects.If they are difficult with you, quote these Regs anyway as it might make them take notice and open up a dialogue with you. Good luck.