Big Ken, you'd (probably) be surprised how often Q's like yours come up in this Section. AND the - very understandable - dilemma you face IF you later find out you don't take to scrolling comes up often too. So you have my sympathies mate.
But the fact is, AFAIK (and that goes for several other members much more knowledgeable than I) you have 2 basic choices (of course!):
1. Wait and see what turns up on "the bay", etc, etc, and take a POSSIBLE risk - there are some real bargains to be had, but also some over-priced lemons, OR;
2. Buy new. If going option 2 then you have a further "sub-choice" to make - buy a "cheapo" so that potential losses are minimised IF you decide to give up later, OR buy a good'un (Hegner is perhaps the best example of a real "R-R machine).
BUT though I'm not in UK I know that at current prices you can easily spend a grand (£s) or more for Hegner, whereas a machine such as you suggest can vary from under a hundred quid (Aldi Lidl, when in stock) to easily a couple of hundred or more. Someone above has said "your" Charnwood looks like his Record, and that's not surprising because it seems that ALL of the below a couple of hundred quid machines come out of the same one or two Chinese factories - usually the difference/s are only colour, badge/s, and the number of "goodies" included/excluded. For example "your" Charnwood includes a light AND a foot switch - both useful accessories IMO - AND the price is "only" <150 quid - not too bad at all.
It would be "more than nice" if that Charnwood will take both pinned and pinless blades (perhaps you can download the Manual and check) but either way, make no mistake, either way it WILL cut(!) AND will be a pretty good (but not the best) intro to scrolling generally.
So IF you go that route and decide that scrolling's not for you, you won't have lost too much, though as already pointed out by someone above, you're likely to only get a few quid for it SH, whereas if you bought a new Hegner (example) and decided to sell that, you'd almost certainly get at least 50% of the new price, perhaps 60% or even more if it was really almost new and in 1st class nick - but that's still a BIG loss against the price of whatever new Hegner model you decided to buy and then compare that to the, say, 100 quid loss you'd have on selling the Charnwood.
As I said at the start it really is a BIG problem to decide for anyone in your position, but I'm afraid all of us "bystanders" can only offer well-meaning advice. It really does depend on what you want/need.
If it's any help at all I had a very old Dremel Moto Shop scroll back in the mid 80's, realised it's limitations, scrapped it in the noughties to buy a similar saw to "your" Charnwood", but when I got "really serious" about scrolling I gave that 2nd machine away to someone who wanted to start off, and bought an Excalibur 21 (NOT the Axminster version) 5 years ago (which at the time cost roughly 700 Euros). Doing my sums I would have saved money if I had bought that at the start, back in the mid 80's, but of course I didn't know then what I know now!!!!!!
All NO help really, I know, but "HTH" anyway, and good luck!