I found this
http/www.fishforums.net/index.php?/topic/414256-my-new-tank-finally-has-fish/ which might be useful as it is the same tank you are considering.
Gumtree is great I recently bought a Juwel Vision 180 with two Eheim external filters plus heater and loads of extras totally approx £700 worth of stuff for £100 and it looks like new. I also got an Aquaone 980 with stand, internal and external filter plus loads of extras, for a fraction of what it would cost new. You need to know what you are doing though when buying secondhand and be prepared to walk away if it is not what you want. I initially bought a smaller Aquaone 320 with stand, heater, filter, fish etc., and when I arrived to look at it the guy had drained the tank and put the fish in a tiny ice cream container. I bought it because I felt the fish were too large for the aquarium (not the ideal reason), but when I got it all home, the filter had not been cleaned out in forever, the heater did not even have a fuse in the plug (I was advised all was working!), the fish were in toxic water and there were other issues. I had to quickly set up an even smaller aquarium to house the fish as my LFS (Local Fish Shop) was closed. I later gave the large catfish to the LFS and he has gone to a very large tank 350L, and the Java Loach is now with others in my 215L and is a lot fatter than when I got it! As for the small aquarium I still have it, but want to replace it.
Do not let this scare you though as buying through Gumtree can be very rewarding as per my Juwel and Aquaone 980. I watched the Juwel for sometime, saw the price drop over time, went to see it up and running with fish in, wanted it without the fish, bought the Aquaone, a week later it dropped by 50% and the fish were gone, too good to miss! So the key here is to ideally see the aquarium up and running (my 980 was not but it was in good condition). Ask questions of the owner and get a "feel" for if they know what they are doing and have looked after the aquarium. Do not take their word on anything but check it for yourself. Anyone genuine with the fishes welfare at the forefront will be happy to talk to you. The best buys are those who just do not have the time anymore (both of my large aquariums) or are moving. As other posters have said if you get one up and running with the fish you have everything you need without all the hassle of waiting for the aquarium to cycle etc. If you do manage to find a good buy then you will need containers to not only transfer the fish but also at least 50%+ of the water (others advise if you think different %). A good container is a beer bucket as these hold about 25-30L, have a lid and are great for later water changes etc.
Re: getting the fish with an aquarium. Remember that the cost of fish can also add up, so if you initially purchase an aquarium with fish this can save you quite a bit. Plus if some of them are not quite what you want then your LFS will usually take what you do not want. They do not usually give you money (may give you food or swap if your lucky) for them but at least it is a good way to part with them. Main thing is look for a set up that matches what you ideally want e.g. tropical community or cichlids.
I agree with other posters that a good fish shop maybe a better option for you as they are in it for the long haul and usually happy to share their knowledge. Do a search on "
East Anglia, Norfolk tropical fish stores" and you will come across some interesting info., whereby others in your area say which shops they go to. For Gumtree search for "
Gumtree Norfolk" then put aquarium in the search on Gumtree, then after you have looked there be sure to then click the Fish Tank(s) links as they will often give extra choices. Just had a quick look and there are a few nice aquariums on there, some are empty but look in good condition and not that old.
Where are you planning to locate your aquarium? If it is in the bedroom make sure the filters etc are ultra quiet.
Of course all of us will have different opinions based on what has worked for us, and you can become overwhelmed, however we are all here to help and want your new hobby to be a success for you, so continue to ask away.
Happy hunting, look forward to hearing more from your journey into a wonderful hobby, although be warned it can be addictive