Though modest by shop standards, even that seems excessive. For an experienced mechanic it should be just minutes, but any shop is going to charge an hour.1.75 hrs billed for removal of old and install of new rear springs and shocks, at my local repair shop.
Just lift, put a screw post under the axle, whiz out two lower shock bolts, drop axle and remove/replace. On a lift it can be done almost as fast as I can write about it
On the ground, jackstands in back, floor jack under the axle, then same. Caution, the jack is just to hold the axle in place to remove the shock bolts. Will have to lower the axle an inch or so. DO Not jack an Insight by this method. A short length of 2x4 on top of jack will spread the jack load if you are concerned.