What would you charge for small LAN setup?

On the side, I repair PCs for people and charge a fair price. One of my clients asked me to set up a LAN for her small business and asked me what I would charge. I told her I would get back with her on that because I have never done that before on the side (I do a little bit of networking at my job).
JOB: LAN for two computers and two printers connected via router, dsl hooked to router/switch.
What would be a fair price? The length of the job should be more or less a hour, in my opinion.

*I’ve tried to find out the price in the area. All I know about that is the one business charges a flat rate, regardless of what is done, of $100.