Honestly, I don't worry about the coins carried that much because micromanaging inventory is a tedious job and I've rarely encountered situations in roleplays where characters are actually buying stuff that isn't just super minor roleplay flavourings like food or the occasional potion. We're not going to throw you in a situation where it's like "that'll be 1,200 septims for the dildo hammer. You'll have that much after 3 missions!"