Simply text this to the removal chap and all will be well:
Being the honourable man that I am, I have a deal to strike with you, the junk removal engineer extraordinaire. I will require a refund of 80 pounds and I wish to receive a text from you, the junk removal engineer, apologising for your extra-curricular pricing behaviour yesterday. If I receive this text without qualification, the deal is struck and you shall retain the extra 10 pounds as a goodwill gesture. Only then will I renew my friendship with Jon-Paul and believe this deal was secured at fair, sensible and rational value. Perhaps then I can finally finished putting stuff in the washing machine. Yours, Army of Harmony.