The one one the bottom left appears to be Sedum morganianum, to the right of it is Kalanchoe tomentosa. The right middle also appears to be some time type of Sedum. The back right appears to be Crassula perforata. Sorry, I don't know the cactus

I THINK that it isn't a bonsai in the true sense of the word, but it is in fact a buxus or box plant., shaped and grown to appear tree like. The trouble is, If I'm right, I don't think the plant is a "dwarf" as such and will just try to grow like normal, which poses two problems, firstly it'll try to grow too big and secondly, the soil won't be enough to sustain it and it will look sickly and eventually die and if you feed it .....it will grow. That said I just THINK that's what it is, it may be worth taking it along to a good garden centre to get a confirmation of what it is first.

Yep I agree. Fantastically easy to grow - they put up with a load of abuse and neglect. They're also super easy to propagate, just cut a bit off, take the leaves off a node and put it in soil, they root in no time.

I think this is Pilea libanensis. Lots of common names including ‘grey artillery plant’ or my favourite ‘silver sprinkles’. Not sure about the clover leaf stems, this could be an entirely separate plant. Two for the price of one! ;)