Last september I purchased an elastic trampoline from Amazon (yellow) for private use.
I wanted the biggest on the market and professional for outdoor all weather all year.
I compared the costs of the two cheaper providers (cheaper than Decatlon and many others found on Google).
we r sports costed additional €75 for shipping to Italy from UK, so I opted for the smaller (15 ft) sixbros from DE.
Scroll to see the whole spreadsheet (Trampline cost and size below). Scroll the bar to see all data.
The interesting aspect of my search is that the cost is linear with the diameter as shown by the graph (Linear trend below), but the trampoline size goes with the square! The obvious saving is a classical economy of scale. In some cases the smaller sizes cost like the larger ones.
For elastic trampolines bigger is better!
