i don't sell chocolates at the moment, but food safety is something i think about and try to keep up in. i worked in a research lab for a while that worked with food safety microbes (mostly in water quality), though i generally worked with bacteria instead of fungi.
if you search the forum, you can find a lot of posts talking about the moisture content and water activity of various confections. broadly speaking, the more water there is in something, the lower the shelf life is going to be (like, a bar of pure chocolate is functionally immortal, a chocolate covered strawberry will only last a little while). as @pastrygirl mentioned, items like caramels and gianduja will usually give less trouble in this area as they'll have much less water than something like a custard-filled bonbon.
when it comes to longer-term storage of stuff, the freezer is really the way to go, as @pastrygirl again suggested. for the most part, it pauses the countdown on shelf life. this only applies to a freezer that doesn't auto-defrost. the defrost cycles in a freezer will degrade food over time (high fat, high sugar, and high alcohol foods are often the least impacted but it's still a non-zero effect); they won't grow microbes while frozen, but they may suffer taste or texture issues after an extended period of time. this effect will vary from freezer to freezer.
something to think about: probably all of us have had something grow mould while refrigerated. the average fridge temp is around 4C, or 39F. if mould can grow at those temperatures, it will surely grow at temperatures above this (well, up to a point). still, the fridge will absolutely extend the shelf life of confections (both in terms of microbial spoilage as well as slower oxidation), though, usually up to several times what they might otherwise be