the command /emas is unavailable to Players normally, you should look into switching it to /em and mention that it's supposed to be set up as a Token Action Macro.

You can include a Selling variable in the Buying an Item Query as a simple

• ?{Selling?|Yes, *(0.5) [Selling]|No, *(1)[Buying]}

with appropriate Parsing applied of course. Then you simply include the Query Call in the appropriate Fields (specifically at the end of the Buying Query's Sum), unless you desire to have separate values for such things, for instance one might be able to spend more/less than 2x they can earn.

Just a suggestion.

https://github.com/poltergeisha/Roll20-Like-A-Boss/blob/master/Macros.md#roll
Typo right at the start of the Macro