Keep the money - if it's for £5000/US$10,000.
Your "friend's" business is based in the UK and from the looks of it unlikely to go global expanding to other countires.
Also remember, other massive/big UK businesses eg. pcworld,co.uk, laptopsdirect,co.uk do not own the .com - doubt they dwell on it too much - so your friend with his far smaller business should take this into consideration.
Other factors:
1/ your "friend" has laptoprepair,co,uk whereas he's offering the PLURAL in .com.
It's a different thing altogether.
2/ laptoprepair,co,uk already has 1st place in the google uk SE.
3/ doubt your frend is losing traffic or a lot of biz b/c he doesn't have the .com
laptoprepairs,com gets mostly US traffic anyway, being an active US site. Any "type-ins" would be close to zero based on OV stats.
4/ Margins on laptop repairs are low AND competitive, constrained by prices of brand new cheap laptops..
5/ to recoup the £5000, 'friend' would have to fix a lot of laptops.
6/ laptoprepairs,com is an active site...so they couldn't make it work/wants out of business?
7/ laptops are getting cheaper and more and more 'disposable'
8/ warranties are getting cheaper / some already include 2 yrs free
9/ Notebook is replacing the word "laptop" slowly but surely eg dell advertising.
10/ presumably they first offered it to laptoprepair,com for $10,000 and they refused it before asking your 'friend'.