I have just bought myself that gorgeous little thing depicted above - a Stagi M5 Anglo-Concertina. For scale; it is hexagonal and about 7 inches diameter across the points, and expands to about 15 inches when the bellow are opened.
I have always (since age about 14) wanted a concertina, but instead I played different free-reed squeeze-boxes; the piano accordion because I could borrow one free from school; and later I got a melodeon, because it was similar to the accordion.
And at the time when I was keenest to get a concertina - there were only available cheap semi-toys, and very expensive hand-made or refurbished antique instruments. "Intermediate" quality concertinas - such as the one I just bought - either did not exist, or were inaccessible.
You may think the melodeon experience ought to help me play the anglo-concertina because they are both push-pull instruments, giving a different note in and out - both use the same diatonic (major key) system of tuning of C and G rows (with assorted accidental notes in the third row to enable playing in some other keys).
And indeed each concertina row of 10 buttons in C or G is the same as the 10 buttons in each row of my melodeon except being arranged with five buttons going up the left side, and down the right side of the concertina - as if the melodeon's right hand buttons had been folded over and cut in half!
But I am actually rather intimidated by this little box! Because I have such a lot to un-learn - which is always much more difficult than merely learning. I am embarrassingly inept, considering the decades of similar experience. Everything I try to play - even the simplest scales or tunes - goes wrong...
It is already apparent that I will need to go right back to basics, and build a technique from the ground upwards. It's going to be a long-haul, no doubt.
That is the challenge - my new quest.