Here's my long explanation of what I have done:
I don't count my initial purchase in my budget. (i actually bought my ego a whole year ago, but the analogs were refusing to let me use it. mostly, I was too scared to quit again) Since I bought it so long ago, that money is long gone, that's why I don't count it. Anyway, every 2 weeks I have been spending my analog money on supplies. Some of my orders are still on the way and haven't arrived yet. But for the total of $153 (i spent $180/month on analogs) and some shopping of sales, I have bought 5 attys, 2 spare battery chargers, and a little over 800ml of juice. I'm going DIY, so about half of that is unflavored, plus the glycerin to dilute it, and the flavoring that I know I love. I also got other odds and ends- extra flavorings to try, a new bigger case for my ego, etc. I am quite set on supplies for a long while.
My first attempt at vaping 2+ years ago, ended in a dramatic failure, when husband did not support my proposed budget, and I could not afford to stock up on extras. I had battery failure, and a charger failure, which resulted in me being back on analogs. I refuse to allow that to happen again, and demanded my full analog budget for vaping supplies. I have nothing I need to buy with my analog money coming from this next check, so that money will sit in a jar and wait until I need it. Or, when I have enough there, I will pay a bill, so husband can see that I am actually spending less money now that I used to be.
If you were saying that your full analog budget wasn't doable because of finances, consider that while smoking, you somehow managed to find that money. I am very, very broke, yet we always found money for cigarettes. Even if you allow yourself only a percentage, say 50%, or 75% of your budget, that would be far better than letting the budget get dropped too low, and not being able to afford replacements for blown attys, etc.
I would suggest that you stick to the full budget (or as close to it as you can manage) until you have a stockpile of supplies and juice capable of getting you through several months. After that point, I would re-evaluate, and see how much $$ you need to maintain that stockpile. For example, I use 90ml of juice a month, so I have to be able to afford at least that much. I don't know what my average cost on batteries and attys will be yet, since I have not blown one yet.