Saying that it depends on what you want to play and the availability of things such as air at your local site.
If you need a gun that runs on CO2 and aren't looking for an electronic gun or to play supair then I'd take the eNMey. If you can use air and are looking for something that will last you a while longer check out the second hand pages on here for a cheap electro gun (ion/etek/older DM)
£70 is a reasonable for an eNMey (don't get a fenix) for that price range you may also find a PMR or an Ion which would both be a step up. Your choice widens again at the £100-150 price range with older DMs, Ego/Geo, Eteks and Ethas which again would all be a step up and last you a tad longer.
For £40 you will get a good hopper, some rotors and Z2s can be had for around that if you are lucky.
£30 should get you a nice aluminium HPA bottle too.