Dont ask for an estimate to repair. Ask the original supplier to replace or repair. If they are not forthcoming or start mentioning the 12 month warranty is up, then mention the "sale of goods act, 1980". A claim under this act supersedes any imposed warrantly term within reason.
An item is expected to be durable as one would reasonably expect. 3 years for an induction hob is not reasonable.
I've had many items replaced this way, normally beyond their original warrany term.