I was talking with my co-DM about weapon trainers, wanting my character Nick to get some training, but there isn't anything that suggested how likely the PCs were to have on available locally. So, I came up with a chart. I'd had a half formed idea already, since several of my players have taken advantage of the weapon training rules, so this really just codified the idea.
Keep in mind, the arrangement of weapons into the different categories is based on my campaign
Chance of finding a weapons trainer in a large town. Chances reduced 50% for small towns, and 75% for villages. Cities add 10% base chance shown below.