You will start saving money at some point. Well, for the most part. Some people (and don't worry Brian and Uma, I won't mention your names) keep buying and buying. LOL If anyone tells you that I'm one of those people who keep buying, don't listen to them. Just because I have more than one juice box mod on order means nothing. Nothing at all. LOL
Okay, seriously, I am on the saving end right now. When I started, I was probably spending more each month on vaping supplies than I was on smoking, but not by much. I started with an M401 unit (spent $70 on that and probably another $50 on cartridges). About a week later I ordered a 901 and some juice (spent $65 there). I used the first unit for two weeks, so that cost me about $40 more than I would have spent on smoking. First lesson learned. The second unit I used for two weeks which saved me about $15. over what I would have spent smoking during that time. I next ordered the 801 with the same results as the 901. Then I ordered the 510 and the VP2 on the same day. I used those units for a couple of months (and saved quite a bit over smoking) before getting the Spade and then a couple of weeks later, the VP/PT. At that time I ordered just over $100.00 worth of juice. But the juice lasted for several months, so although I spent a lot up front, you have to figure out how long it will last. After another month I had to try this new device called the eGo. Everyone was raving about it, so I got one. It was the device that was perfect for me. I was completely satisfied so I didn't buy anything else for 4 months - except for attys. I bought a Black Silver Bullet then because I'd heard so much good about it. Between my BSB and ego, I didn't feel the need for any other devices for the next 7 months. Then I realized that those really weren't enough backups and I ordered a Provape1. At that point I figured I was done. Until I heard about the new juice boxes available and ordered those. See what I mean? But I probably won't buy another unit for quite some time now. I know I've saved hundreds at this point, so even though I've spent quite a bit in the last two months (because I've also started stocking up on more attys lately), I'm still on the savings end of things. Once you find the perfect unit or units, all you really need to buy is attys and juice. If you start out with the right unit (unlike me), you can be saving within weeks. I never worried too much about what I was spending (although I did try to keep it at or below what I would have spent smoking) because I considered it an investment in my health. I still feel that way about it.
As far as backups go, it's a good idea to have at least 3 batteries on hand. If you only have two and one dies, then you don't have anything to vape while the one battery charges. That won't be the case if you have 3. Attys, I would recommend having at least 5 on hand at once. Juice...depends on how much you use. Figure out how much you'll use in a week, multiply that by four so you know how much you'll use in a month and then keep at least a months worth on hand. I kept 6 months worth on hand at first - more now. A backup charger is a really good idea. If your charger dies, then you have no way of vaping when a battery dies. I have a car charger, too. If the power goes out, I don't have to worry about not being able to charge a battery. And I have an adapter so I can plug in and vape in the car.
As far as all the, better, more powerful, variable voltage, cool, nifty, just gotta have them, new units...well, if you are like some people I know, you just won't be able to help yourself. But you can still be saving money.