Ashley Douglas, 23, called out the emergency tradesman when he found his kitchen flooded at 1am.
A pipe had burst under his sink and water was pouring into his new two-bed semi.
Ashley claims Mehdi Peiravi, boss of AM PM Plumbers, ignored questions about how much the work was going to cost — and then hit him with the huge £3862.80 bill.
He charged £288 for parts and an eye-watering £3,574.80 for labour and the call-out.
Peiravi also demanded Ashley pay up on the spot.
Yesterday, the unrepentant plumber, 29, stuck by his bill.
He claimed he spent two hours and 45 minutes on the job.
He told The Sun: “I will charge £1million per hour if I like, it’s nobody’s business.
“I charge on the basis of expertise and knowledge. I decide my prices, I won’t be giving anybody any refunds.”
Ashley, who lives in Hook, Hants, said: “I was gobsmacked, this bloke had come into my house and started demanding all this money.
“I was quite intimidated, he wouldn’t tell me how much it would cost until he’d finished and then told me I had to pay.”
Neil Douglas, 34, who runs ND Plumbing Services in Whitchurch, said the job should have cost £260 and taken less than an hour
He added: “Ashley was totally ripped off.”