[Geoff F]

Going by the size and your photos I think that Steatoda nobilis is a possibility. Your photos look a bit dark all over but I think that females can be a bit less well defined colourwise and the characeristic paler edge to the front of the abdomen may well be hidden by the camera angle.

The better marked specimens could be males, about 10mm head to tail.

So just in case this is correct, don't pick them up for a better look; they won't be a problem otherwise.

Despite living in the far south of Devon, this is one species that I haven't found so far.

For the large brownish spider have a look at Tegenaria sp. The habitat sounds OK for T. duellica but they are rather variable in colour and it is difficult to seperate the species from a photo or just by looking at them. Alternately there are a few larger Wolf Spiders, Lycosidae family, but I'm a bit doubtful. The same goes for Pisaura mirabilis.

On the other hand, Araneus quadratus sounds possible but, as far as I am aware, it is more normally found in a web. But certainly worth a look.