Many mechanics get the terms strut and shock confused. They are not much different because they do the same thing but the set up for each is different. Please see the attached for more detail.
The only reason you need to replace them is if they are leaking. Sometimes the mounting rubber wears out and needs replacing but this is rare.
It is also unlikely, that all 4 fail at the same time. So I would ask why they are saying they need replaced. If they are leaking then they are correct that they need to be replaced. If not, then I would not recommend replacement.
As for how much it should cost. The parts range in price based on brand but the labor should be about an hour for each one. This means you take their door rate and multiply it by 3.5-4 hours if doing all of them and this should give you the approximate labor cost. Then just add the parts and that will be your price.
Please let me know if you have questions. Thanks
Images (Click to enlarge)
Tuesday, August 20th, 2019 AT 4:29 PM