There are hobbyists who, although they may know something about fixing computers, are not qualified to take care of your machines. Choose a factory-certified technician with a lot of experience so that your computer problems will be fixed rather than made worse.
Before choosing a company, check their reputation in the community. If they have provided services for others with quality results, then they can probably take care of your machines as well.
Always ask for references before choosing to work with a company. You can ask questions of previous clients to make sure that your machines will be safe. Companies who offer virus protection and removal as well are usually more stable and competent and more likely to have contracts with the major security firms.
To learn more about what your computer maintenance contract should include read, Computer Maintenance Contracts: They Aren’t All the Same (link above).
Blogged by Computer Consulting 101 Professional Kit