Selling paintings

[Arthur Campling]

Hello! I’m planning an exhibition with character paintings like the one bellow to sell at local, less formal galleries and maybe online (but rather not).

Is there a market for this style, and do they need to look more polished?

Should I stick to a fantasy theme, or can I mix themes if I use the same medium?
I’ve noticed most exhibitions focus on one theme. What’s your advice?

Thanks guys!