They're just insulting me more

Hi. Recently I've heard about phone recycling companies and found that it would be a good idea to sell some of my and my fiancee's used phones to them. Our first and final attempt was iPhone 3g 8gb which was sent to them in hope to get some money in return. The initial quote for our iphone was 30 pounds from Gadgets4everyone.co.uk, we selected this company through comparemymobile.co.uk because of the best offer. Before it was sent, we charged it, erased all our private data and made sure that it is fully functional. We were positive about the experience at the beginning since we got a quick response after they received our phone. The main idea of that response was that they will do several tests with our phone in order to check if it's functional and suits their offer. Since then, problems have occurred. 1. No response around changes in phone conditions and price changes from testing period The last response with price from them was when they put us on to the payment queue, which stated that we will get 0.00 pounds. 2. Not answering phone calls and emails. After we were shocked with the price we got, we started calling them, non-stop, during their working hours, nobody answered... Emails were ignored. 3. Somehow we managed to get in touch with them. Still, they've lied about the conditions of our phone. Our phone was fully functional till it got to them, they've explained such a significant price drop by stating that our phone isn't charging and has many scratches on the back and so forth.... This was an absolute LIE. And because of their terms&conditions they were ready to recycle it for FREE. 4. They offered to send it back for extra pay. They generally started sucking more money from us. Since we were unsatisfied with their decision, they said that they do returns. We had to send them money to get our phone back and I don't really think that their postage charges were reasonable. 5. WHEN WE GOT OUR PHONE BACK..... Well, I think they wanted to avoid their fake tales and turn them into reality just not to get caught on false statements they make. Seems like they scratched our phone with sandpaper. It's now a total waste in general... NOT WORKING, NOT CHARGING, SCRATCHED iPHONE that was fully functional, chargeable and had just few minor scratches. I feel totally ripped-off and have no idea what to do since there were no receipts so far or paperwork incurred, just email conversation. I've sent them an email about this and they've just ignored it. Their office is also far from our town, so I have no chances to 'shake hands' with them, unfortunately... I'm shocked that I've paid to get our phone in such a terrible condition. I'll be very thankful if there is any advice on what to do.