I don't get these kind of posts.
You initially simply plan to reinstall Windows over an existing installation and keep all data there while you know there's a virus. It's a well known fact that even by applying virus "removers" it's always best to do a clean Windows reinstall to make sure there's a fresh and clean set of Windows files being used.
You look up on the Internet on what to do with "some" sort of virus and you install crap software. That on itself can even make things worse.
You deliver the laptop back with the assessment that all infections were removed using one bit of software and that simply the Internet worked again.
If you receive a virus infected computer (regardless of whether it's Windows, Mac, ...) you:
- back-up the data (not the full hard disk) in off-line mode
- run a virus scan with known good software on that off-line data
- you wipe the original HD and do a fresh Windows install
- you install proper AV software (there's very good free software available)
- you copy back the data
- you run a final scan
Being pissed off because the clients asked you to fix it after having returned a non fixed machine is not justifiable. The client paid for it and expects it to be fixed. The fact you only requested a very limited amount of money is a nice gesture but doesn't mean the client cannot expect a properly fixed computer. If you know your price doesn't cut the work that you spend (or spent) on it, then increase your price or don't take such work.
This^^^
You clearly don't know anything about Windows computers.