This is my first summer with my new greenhouse and I am thinking about shading. Does anyone have any advise on the best options?
The cheapest option is the spray on stuff. Spray on carefully, on the outside of the glass, so it doesn't look too messy, then just brush off with a soft brush in the autumn. Shade netting looks a bit nicer, but is a bit fiddly to put up. Much easier if you have a wooden greenhouse rather than a metal one. When you take it down you'll have to label all the bits or start from scratch next year. If your budget will stretch to it you can get the roller blind version, but I've no experience of that!
Having spent hours fixing shading year after year one year I gave it a miss, had the best tomato's ever so gave up doing it. My greenhouse a lean toward South facing has lots of vents, retirement means you can open doors and vents as needed to keep a level oh heat, watering the floor during the hot part of the day plus a couple of buckets of water standing next to the platnts works for me and has done for a lot of years. The shading went in the bin.
I just leave my winter bubble wrap up, insulates winter and summer.