'05 Jimny Key fob problem (Again)

So the open button died and gone to keyfob heaven...
Went to the horses mouth, and he had a look. took it apart and pressed the button in front of a hand held
scanner, saw that 'shut' button is working ok. That's when I asked him for a price and answer was a surprisingly
low 91 quid. What you guys think? the fob is 15 years old fair do's....

Remove battery, soak the button in contact cleaner and work the button whilst it's soaked. Repeat a few times, let it dry and fit battery.
If it works- bingo you are 91 quid better off.
It sounds like (and usually is) a dirty button. If it makes it work keep repeating till it's really clean, may take a few goes. Just a quick spray with cleaner will not work, you need the sequence above.
If it's still dead how much is a button and can you solder?