Reminder to sell mod

[Emmaleah]

I would like something that ideally says "You have X empty bag slots" in flashing red (combat text) letters on my screen whenever I am in an area where there is the resting xp gain (cities/inns). It would be nice if it would also say this whenever I visit a vendor, bank or mailbox (user toggled individually) "X" would also be definable by the user.

I know nothing about making WoW mods, I did some UI mods using XML in EQ but that appears to be soooo different. I also have other minor programming experience and I would be willing to try and make it myself but I really dont have a clue where to start.