The amount of time you can spend leveling, grinding, or farming is influenced by bag space. Your ability to craft can be related to the variety of materials you have stored. Your flexibility between roles (main heals, raid heals, DPS, tank, pvp) can be related to your various gear sets, which take bag space. Proper Inventory management saves you time and currency, plus gives room for those 25 tabards you just could never toss out!
While leveling, do everything in your power to use Bags that do not Bind (no Bind on Equip). The two best deals are and which I always buy if I see them at 7g or less. Quest reward bags are an exception, but for many alts these will be too small and too late. Only upgrade to Bind on Equip bags that are 20 slots or more, 28 or more for crafting specific ones.
Open a Bank Account
The twenty-eight 28 free slots in your bank can fill quickly. The first three additional bag slots in your bank cost 11 gold 10 silver total. All the future slots cost 25g a pop. So, focus on the first three, use your smallest extra bags. If your main has cash to spare, use two 16 slot bags that do not bind, and a larger 28 slot crafting bag (mining, leatherworking, herbs, or enchanting)
Join the Club
A guild bank, with two or three bank tabs is super. Two tabs cost 350g for 196 slots (1g79s each), three tabs cost 850g for slots (2.89g each). Compare this to the price of one 22 slot , costing 700g to 1000g and often just an upgrade/replacement of a 16 slot bag, a net gain of 6 slots at a cost of 115g to 167g for each!
An example level 1 bank alt might have the following setup:
- a 16 slot starter back pack
- four 16 slot mooncloth bags
- a bank (28 slots)
- a 28 slot enchanting bag
- a 28 slot mining bag
- a 28 slot leatherworking bag
- guild with two bank tabs (196 slots)
For a total of 388 slots at a cost of about 850g, or about 2.14g each slot (assuming all bags bought on AH).
Replace the crafting specific bags with 16 slot bags, for 352 slots at 400g or about 1.13g each.
Use the other four bank bag slots before buiying that 3rd guild bank tab. Add four bank slots (100g) with four 16 slot bags (28g), yields 64 more slots for 128g == 2g each.
Why calculate cost per slot? To save you money, and help decide whether to store something at all. If you have a bag space cost of 2.5g, and have 3 mild spices ... do you put them in your bank? Heck no.