The job is replacing a new shower tray

Why does he require to be paid up front? Signature or not, its a question of principle?? What if you are unhappy with his work? Regards Neil

I’d ask him to sign it before hand over cash 😀

it is up to you ,most of us ask for a deposit to start the job.

Don’t pay anything upfront any reputable company will have accounts with builders merchants for the materials and for a job that size the contractor could wait until completed to be paid as you may not be happy with the work completed

Work schedule, payment plan, invoice, bank transfer.