OT: Cat 5 Install Pricing

Hi everyone, I know this is a bit off topic, but I don't know a good group 
to ask this in.

I've done PC repair work as a side business on the weekends for years now 
and recently I have a customer that wants me to install a network in a
small 
dentist office.  It is a new building and I will be installing 10
computers. 
There will be a computer at all 6 dental chairs one at the x-ray machine
and 
3 in the receptionist area.  The office is not large, about 50 feet by 30 
feet and the conduit and boxes are installed for the cable. I just have to

pull the conduit and tack it up above the dropped ceiling and of course
add 
connectors to the ends.

My question is how much should I charge for pulling and installing cat 5 
cable in this situation. I have been given all sorts of suggestions from 
$20/ft to $75 per cable drop. $20 per foot seems outrageous to me, but 
that's why I'm asking.

TIA.

Mike