I wouldn't go on your own to collect, make sure you take a couple of friends.
We bought a Brooklands kit for my Range Rover, since sold, and we had the same thing cash on collection wouldn't give an address etc. A friend of ours volunteered to collect it for us as it was in the Bristol area and we are in North Yorkshire and a relay was organised to get it to us. He contacted the guy and arranged a meet, he took a mate with him and when he arrived at the meet the guy was there with 2 other dodgy looking blokes, he said afterwards he was glad he took his "big" mate with him as the area they met in was a bit dodgy.