Answer:
Repair Technician (this is a guess, since im also on this)
Explanation:
A repair technician work alone most of the time and since he is good with computers, he can fix computers and not have to worry about working with others if he is too good at it, since he will satisfy so many customers and make alot of money if it is based on fixing a problem on a Computer. Since he is good with numbers, he will be able to count the fee from him having to work and fix something based on what it is.