A friends flat is overlooked by other flats and they want to put up some
japanese type opaque paper and also some reflective film ( the type you can
look out of, but people looking in only see a silvery reflection) on to the
window glass.

Could greaseproof cooking paper be used instead of japanese paper (since its
probably a lot cheaper) and if so what would be a way to stick it to the
glass so that it could be easily removed?

Would anyone know where in London the reflective film can be bought?
Thanks.