1000 septims weigh 1 lb. There are regional banks to deposit money into, and you may trade large sums in for letters of credit for 10%.
DR: If you use a stronger material type it counts as all previous type’s of material as well.
Retraining costs(but not time) is increased by 2x’s, but maybe less if your of a higher rank with them. If your a non-faction member the trainer will charge anywhere from x3 to x4 depending on your reputation with the faction.