I've never had a problem with gold (except when it comes to mounts), here is how I level though so it may be different then what you are doing.

I level all my toons together and I quest. I generally give the main toon of any group 50g to start. This is for initial training and bags and misc. stuff.

I never buy equipment. I noticed you said "training and gear x 4". Running around with four (or three in your case) toons following you... better gear is just over rated until you hit 70. You will be replacing that gear so quickly it doesn't make sense to buy gear on the AH. An exception would be wands but that is just me, I get them the best wands I can as soon as possible as four wands going will burn down most things and you can save a lot of mana.

Always have at least one enchanter with you so that any BOP items that your group doesn't need or can't use can be sharded for the mats and sold on AH.

Stay away from professions (other than enchanting or gathering professions) as they are money sinks unless you don't purchase mats off the AH and even then those mats are ones that you could be selling instead of using.

I do give the main the starter cash but before long I have made that back up and then some.

1) Don't buy equipment.
2) Do quests.
3) DON'T BUY EQUIPMENT.

I seriously don't know how you went through 800g. If this is where boosting gets you (or just running instance after instance) I am glad I went the questing route.