Chantelle,I understand where you are coming from in trying to cover some of the ferry and fuel costs,but please be very careful taking anything back into the UK.The tobacco and drug barons thrive on guys like yourself and book in a couple of cubic metres to go back and the boxes could be full of cigarettes or worse drugs.
If you get stopped by Customs at the UK port,the first thing they ask you is what you are carrying and is it your own goods.If you say that it is your stuff and they search and find any contraband,you are in trouble.If you then try and say that it`s a customers or a friends,they will just say that 5 minutes ago you said it was your own.Having ascertained that you are carrying goods for someone else,you then fall into the trap of not being insured to carry goods for profit.
Also if you have an accident then the customers goods will not be insured and you could be faced with having to pay out a considerable sum of money to the person whose goods you are carrying.
If you do go ahead and take some stuff back,good luck to you but at least print out a document on Microsoft Word or something for the customer to sign and have them declare that they packed the boxes personally and that they contain no drugs,alcohol,tobacco,firearms or any illegal substance and make them put on a pick up address,delivery address and passport number..It will be the only protection you have should any of the above items be discovered if you get a search.
I`ve been doing this now for 8 years and have been searched many times by Customs and fortuneately never had any illegal goods onboard,but I am fairly vigilant on checking what goes on my lorry myself and have in fact refused to take stuff in the past because of bad vibes.I would rather not earn that bit of money than end up in handcuffs.
Please don`t think this is a sour grapes posting it`s not,I`m as busy as I want to be and my lorry is always pretty full if not completely full and I can take 59 m3.It`s a genuine warning to be careful when taking stuff back.
Just a couple of months ago an aquaintance of mine had his lorry impounded when it was found to have both cocaine and cannabis on board.
Good luck and most importantly have a safe trip.