Ye Magick Shoppe for 5E
Your players’ ship arrives at the docks at last. They go up to the first stevedore or whombler they see and say: ‘Excuse me there, hard working fellow - but where is the local magic shop?’:
Suddenly this all takes a sharp turn and the DM goes 'Out Of Character’: “What? Magic shop?” You kindly explain that there isn’t such a thing. Says so right there in the DMG, see? It is impossible for one to exist in a 5e D&D world. Period.
Your sassy players do not give up. Someone points out such shops exist here in reality on Earth, despite having no provable magic. There are even different kinds (lots sell incense and religious stuff, some selling bits o’ stone, people may want to stare at your crystal balls and it just goes wild from there). They point out a variant human’s feat can give any commoner a bunch of cantrips and one first level spell. So why doesn’t anyone own anything enchanted?
This guide gives you RaW self-defense. You can have as many magic shops as you like without breaking any rules. The trick is to put items in them that are interesting, fun and even useful despite the fact that almost nothing is an uncommon or rare magic item.