My cacti are loving the weather in the uk at the moment and so am I
...but I am very aware of the impending winter and how cold it was here last year. The temperature was hitting -10c (14f) here overnight and not getting over 0 (32f) daytime for a period of about 2 weeks. Either side of those two weeks, it was maybe 5c warmer but with the same kind of swing. Minus temps are expected usually for about 2 months. Not constant and usually the daytime temps are at least single figures. It was exceptional but I guess I have to bank on the worst rather than the best to minimise damage. 
I am planning on a Greenhouse before autumn, want to tuck em up for the winter, I currently have a cheap polytunnel (boy was that an epic fail of a purchase) but have some questions as I have not had a greenhouse before and want to right rather than replace. I have over 100 plants so inside isn't an option sadly.
Firstly, anyone in the UK have a recommended supplier or brand that I should have a look at?
Or the best type of greenhouse that I should search for? I have seen some Ali and Poly greenhouses quite reasonably priced (but have the feeling that if I think the price is reasonable, it is probably cheap and therefore not up to the job
) These ones don't come with a base and when I spoke to the supplier, he said it secures to the ground with tent type pegs but I could use a wooden plinth if I wanted???We are happy to put in a concrete base if needed or lay flags but as a novice to this I wanted some advice about the best way to go about this. Oh and the space I have is approx 3.5m by 2m (although I could pinch a little more space but don't tell my OH
) Your advice is much appreciate in advance
