Thanks for the replies

My mate paid the guy by Bank transfer, so there is a receipt as such just not exactly for the exhaust itself.

I was curious wether I should atleast see a solicitor and try to take it to a small claims court although I assume it is for my mate to do as it wasn't me that purchased it.

Thanks Dangerous for that advice

Other options mentioned are also worth considering although taking the exhuast then hiding it wont be much use as I need it within a month but cheers

For now I'll leave it up to my mate to try and sort out over the phone, IF he gets no where then we'll more than likely try a solicitor