Would you not consider purchasing a tester and do the tests yourself?
One of you could go on the course, its only a day and quite cheap (perhaps the one with the most general knowledge about electrics would be the best)...only to make it easier! The course will guide the tester through the tests involved and the different appliances etc etc, also the readings you should expect.
As far as i know, if you can show you are a competent tester and you have a course certificate and you show all your pat test logs for the appliances tested, its legal!
Tester basic about 400
Course about 120
appliances tested from then on...free!
Most appliance testers come with software to print results on the pc so its easy!
If ten of you got together in one area, it woulnt cost too much?
Just thinking out loud as a sparkie But i realise it all depends on how much you pay gettin it done/how much kit you have
