creative advice

[STM1993]

The goal is to just avoid losing 5 silver per horse.

If the horse fee is paid while entering the station, then the best thing you can do is to set up a distraction like a fire, and then in the ensuing chaos move the horses in as if you've already paid.

Otherwise, I can't really see a good plan where you need to sneak horses with a meticulous record keeper and two horse loaders who'd remember how many they loaded. Plus, if they distrust you, all they have to do is look into the carriage and check the number of horses. In that case, I'd rather you just pay the 5 silver and then mug it back off whoever you paid it.