Most places like Kwikfit etc wont fit tyres they havent sold, unless you get a bit of a geeza wholl sort you out for cash. One I went to said to the young lad (who was obviously the newly acquired slave) to get em on and for me to pay him cash. He did, and I did, and he was well happy with 15quid!!
If anyones in braintree, the best place is the one first on the right as you go into the industrial estate off the roundabout on the Rayne bypass-y bit. He has no problems whatsoever...