:-\
I just inherited my greenhouse with my new plot. I have never had one before, so was well chuffed to find that replacing panes is not as scary or difficult as it sounds! Three panes had blown out of mine, including a triangular one which looked even more awkward to me! Lovely guy on the site came and showed me how to do the first one and left me to it with the others. Pair of gloves, pair of pliers and it was done! Just new clips required, and new panes which I found in the shed (lucky me!) but i dont think greenhouse glass is very expensive? Have a go, if I can do it anyone can and it would be better than tape in the long run.
;)