Funny, I used to get a lot of 'flat tyres' and got sick of it so I bought a CCTV system. I only had one set of trick or treaters last night and they were about 6.
BTW, if you get any sort of dye on UPVC you need to get it off straight away as the stuff stains badly. one of my neighbours had their windows hit by a poster piant water bomb and it made a real mess.