The maximum towing MAM (Maximum Authorised Mass) of your Jazz (depending on model) is 1000kg braked or 450kg un-braked. 450kg isn't very much by the time you've subtracted the self weight of the trailer which means that realistically you're looking at a braked trailer, that's just added massively to the cost of the trailer.
Then there's the legal aspect, as you're 17 you can only tow a maximum of 750kg on your standard car licence (cat B), to tow any more you will need cat B+E (car unto 3500kg + trailer up to 3500kg)on you're licence, when I did mine more than 3 years ago it cost me about £400 by the time I'd done the training and sat the test. It's the same as an arctic truck test, but in a different vehicle so is much harder than your car test to pass.
You say that the suspension of your car isn't really happy with the current weight of your kit, a trailer of the size you're talking about isn't massively going to help that as it'll probably be single axle and so you'll still have a relatively high rear axle load on your car.
Now you've not only got to insure your car for business but also the trailer, and it's contents. And try and get a trailer down the back of some venues, bet that's not going to be easy.
Sorry to throw a spanner in the works but to stay legal it's gonna get really expensive.