No, they usually won't remove carpets, seats and all that. You
prob can request, but it will cost $$$$. The labour required is
quite a lot. By itself, workshops already charge for labour for
removing seat, removing dashboard, remove carpet etc... imagine
doing all. Prob can get bulk price, but at least few hundred. Also,
dunno if they put back nicely.
They usually don't sandpaper also, but can request, costs
$$$$.
Normally they will spray exterior, engine bay, door internal
lining, boot internal etc.. good enough.
Why bother to strip everything then spray? Half of the places will
never see sunlight again. Waste $$.