yes the price is reasonable and if they know what they are doing the seal will be as it was when it stuck shut,i would not recomend you try to do it yourself as it is a tricky job,depending on lock that is stuck and you can use vasaline to lubricate all moving parts of the locks on your windows and doors,if anymore of your windows and doors are hard to lock the same thing could happen to them as your putting to much stress on the gearbox's or lock mechanisms.hope this helps
shaun www.sdwupvcrepair.co.uk
March 2008