How much do you charge for job's ?

All your overheads ie wages,heat,light,rent,rates and profit should be covered by your hourly labour rate. Any profit made on parts is the icing.
I always used book times as a rough guide age and condition of vehicle got factored in and if I didn't want to do a job I just banged the labour rate up.
Charge enough for labour and a bad job becomes a good job
Almost 20 years ago I charged £50 an hour, the local VW dealer was £109 an hour for comparison ...

Another point to note about book times are that those times are averaged over each job being done by a properly experienced person with all the correct tools and working facilities. So changing a front telescopic strut shocker say 1 hour would have been carried out ten times to reach that time for the job. 

At the moment I'm working on a Peugeot 407 SW where both front springs are broken and one shocker is leaking badly. Initially when I looked at the suspension setup I thought them springs and shockers are going to be a nigh-mare to remove and exchange. AD advises 2.40 hours to change both front shocks and springs. After removing the road wheels today and weighing up the job, I removed the screen scuttle panel and the suspension strut turret plastic mounting covers. I then loosened the three 13 mm nuts that secure the shocker to the turret. There are three more bolts about 18 mm that retain the front suspension wheel hub etc in place. You don't want to remove them. Take off the anti-roll bar link rod completely and remove the centre nut that secures the driveshaft CV joint. Remove the torx bolt that secures the wiring to the suspension and remove the bolt through the lower arm bush. The suspension vertical frame will now move outwards and allow the shocker and spring to come out from behind. I've never done this job before but based on the time it took me this afternoon if all went okay, I'd probably achieve book time now I know what needs to be done. 

Sometimes its not the book time that is the problem, its having all the correct tooling and know how to just get on with it. PMA