I am relatively new to Pathfinder society, but I have been getting my feet wet by both DMing and playing. I just want to make sure that I am not missing any rules when it comes to multiclassing. I may be mixing up house rules that I've experienced in the past with anything that is actually in PFS.
Is there a minimum to how many levels you can take in a class? For example, could all 12 of your levels be in a different class? (I don't know if that is even possible or why you would want to do so. It's just to get the point across.) Is there a minimum number of levels you have to take in any prestige class?
Just for some background on the question I am playing a deaf gnome oracle. I took the Amateur Gunsliger feat once she hit third level. She is a bookbinder and has a small shop in Absalom. The back story for the feat involves receiving a somewhat battered package at her shop. (Writing on the partially torn package had an FR and then an AGILE. So she has spent some time looking for a Father or Friar Agile.) What she doesn't know is the strange parts and pieces in the box come together to complete a dragon pistol.
At fifth level I plan to take a level of gunslinger with the Mysterious Stranger archetype if possible. She only has a 10 wisdom so she wouldn't have much grit otherwise. My thought is finally at fifth she fits the pieces together and discovers, "Whoa this is some kind of crazy crossbow". She then goes about her merry way being an oracle.
I even thought about taking throw anything so if the gun jams she can freak, throw it at the bad guy, then try to hide. In full disclosure she only has a 12 or 13 dexterity right now. I honestly forget off the top of my head. So this is all more that it will be fun for me. I will have plenty of healing and puffs so the parties I play with don't feel that I am a drain on resources with no usefulness.
Would it be okay to take just one level of gunslingers and not look silly or cheesy or other bad things my fellow gamers approve of?