Nice to find this as I'm new on here. I used to think so too, that how could nine notes not be a load of frustration, but I ended up getting into it and producing a piece called Moon Cradle for bagpipes, string quartet, guitar etc.
You're right it does only have nine notes, but it's amazing how far they go. Best to go for an instrument with a few more though!

If it is for the sake of portability you are looking then there are many but main is the love of you for the music, which tune you are looking into? There are so many musical instruments in this world and so many varieties in music. You can log into many online teaching sessions available online now a days. The fees are also very pocket friendly. You can take the lessons in your own time and also can pay the fees in your best understood package.

Try out the double mijwiz, if you get a nice one you can tune them a fifth off and I think that can give you two octaves. However, they're commonly tuned in unison (or close to unison if you go cheap).