Since I've been on this forum last few days I've noticed a lot of you guys advise getting c and c cages as you can make them as big as you want, I'm in the uk so where and how do I go about making one all info greatly appreciated and photos if you could!
Idk about where in the UK you can get them, but I ordered the Whitmor grid shelving unit from Amazon for the US. It was just $20 for 23 grids, which I think is about 17 euros, and then I bought a sheet of corrugated plastic from a hardware store here, for about $10, which is like 9 euros. The grids I got are 14 by 14 inches, and fasten together really easily, like legos or tinker toys if you ever played with those.
Anyways, I really recommend buying a GRID SHELVING SYSTEM, because that's basically what the C&C cages are on the website, only they charge you so so so much more. Then look for a sheet of corrugated plastic to use as a base. Once I got my grids, I made the cage 2x2 grids, with a top and a bottom, and had it lifted up so there's a shelf underneath. I wanted to make it 2x3 grids, but I had to sacrifice space to keep my Tuulikki safe from the cat. The corrugated plastic was smaller than I wanted, but it works alright, you make it into a shallow box and place it in the cage. I line mine with a few layers of newspaper and then anti-pill fleece on top.
If you don't have any other pets that might break into the cage, then you don't need a top to the cage since guinea pigs can't jump over it. Also, if you're not gonna have it set up on shelves, then you don't need a bottom either because you'll have the plastic liner. It's really easy to put together, and relatively cheap if you know where to get the right materials. I'll take a picture and post it later!