Billing people for your time is normal. Our industry has been operating abnormally for too long. Your clients will either continue to call you and pay their bill or they will stop calling you 1-3 times a year for 10-50 minutes making it a non issue.
Many clients will all of a sudden be able to unplug a cable box and plug it back up on their own. Others will learn that they can reboot a modem or router without placing a phone call....others...are more than happy to pay for your help.
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