Yes taxes will be your biggest worry. A quick way to make cash is to put out a add stating you will make his or her computer faster than it already is. Most of that can be cleaned up with tools on one cd, then charge extra to put in some old RAM you salvaged. Clean out the start up, defrag,bam instant $25-30. hour-minimum(house calls)

I read them in the paper all the time, private homes offering some type of comp repair. I know for a fact that you can charge atleast 40 dollars to install some type of wireless set ups or to install anything period. When I was in highschool I worked afternoons and weekends at a comp repair store, the main reason someones comp would not turn on was a bad CPU fan they would charge 50 dollars for parts and labor for a 8 dollar fan and 20 minutes worth of work.