£18.50 to fit a watch battery!

jimpwarsop

Poundland will have a card of various sizes of button batteries.

Ebay will show any number of Chinese watches under a fiver.

https://www.amazon.co.uk/Assorted-Mixed-Alkaline-Button-Batteries/dp/B07GCHC3PD/ref=asc_df_B07GCHC3PD/?tag=googshopuk-21&linkCode=df0&hvadid=394316852066&hvpos=&hvnetw=g&hvrand=16642819822873946503&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=1006586&hvtargid=pla-871930859981&psc=1&tag=&ref=&adgrpid=87233666292&hvpone=&hvptwo=&hvadid=394316852066&hvpos=&hvnetw=g&hvrand=16642819822873946503&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=1006586&hvtargid=pla-871930859981

robatwork

I have one of these Watch Back Case Opener Remove Removal Knife Repair Tool Teenitor Stainless Steel | eBay 
It's coped with all but 1 watch that had to go to a professional for a new battery. Agreed £18.50 is a bit steep. Your local independent jeweller may well be cheaper.

lemondrops69

At our local jewellers you can see them changing the batteries, I've never done it but there is a sign that says 'Watch batteries fitted here' Doesn't sound very exciting