We finally took the plunge and invested in a 6ft trampoline to fit in our postage stamp sized garden. (Ours was from Amazon.co.uk.)We bought ours because it is good fun and in moving back to the UK we have moved away from both a fantastic park but also a massive soft-play place which is in a converted factory in Hengelo NL and had its own trampolines.
Did you know that trampolining is also great for exercising the eye muscles? Two of our friends got theirs after it was suggested as helping "lazy-eyes" because the eyes have to constantly minutely adjust as you bounce up and down. Horse-riding is also good for the same reason. It is so good that one of our friends was told the only hope for her son was an operation by one consultant and when she got a second opinion and tried the trampoline for a year the improvement was such that he doesn't need the op anymore.
Took an afternoon to fit together and is a huge hit.