they shouldnt do but insurance companys are a law to themselfs
in there estimate will be
brand new quarter panel (must be from the
dealer!) wont get copy panels
the labour charge and this wont be back street
garage prices be in region of 75-100 a hour
to take rear quarter off and put back on your looking at 10 hours plus about 6hrs for paint /prep maybe few more if have to blend into adjacent panel
so u be looking at £1500 quid in labour alone
and prob 250-400 for new quarter (off the top of my head dunno how much are from the stealers but bet aint cheap)
u in big cost of the car
personaly i would pull the dent out fill ,sand, refinish
but insurance is another game because if filler cracks or defects due to filler/repair process u will want it sorting again so they like to replace panels