Congratulations; and welcome to the ECF community!
Actually, 500 DKK is equal to 74.57 USD (today's exchange rates... and don't be impressed; I looked it up

), if that takes any more of the sting out of it.
There are all sorts of ways to save money when vaping. From the hardware side, the two biggies are self-control (don't go chasing every new battery, mod, and atty; and learn how to optimize the equipment you have) and build your own coils.
Coil building can be as simple as wrapping some wire (kanthal, stainless steel, etc.) around an inexpensive jeweler's screwdriver and then threading it with some cotton. End cost? just a few cents. As this thread is in the DIY e-liquid sub forum; I will let it go at that.
Saving money from a DIY e-liquid standpoint also has lots of ways to save, or not save, depending on what your end goals are.
If money is your biggest concern; doing a super simple unflavored mix (just PG, VG, and nicotine) is about as easy, and cheap, as you can get. It meets any nicotine dependence you may have, many find it rather pleasant to vape (it has just a hint of sweet to it), and it is dirt cheap (especially if you buy the ingredients in bulk). My current unflavored mix costs me $0.007706 USD/milliliter (that's right; less than 1 cent per mL) because I buy my PG and VG by the gallon, and my nicotine by the liter.
If you are all about taste; then it will be more expensive. Flavor concentrates can be as, or even more, expensive than the nicotine (per mL; because you usually don't buy in nearly as large of quantities). Then,
if you really become a flavor hound, you start feeling the need to buy 20 different "strawberry" flavor concentrates, from 13 different flavor manufacturers, just to get that "perfect" strawberry. Now multiply that by 20 or 30 flavors.
Now, add to that, if you want to chase clouds. So now, instead of going through 5-15mL of a higher nicotine-containing e-liquid, you are going through 30-50mL a day of a lower nicotine-containing e-liquid which you still have to flavor. You see where this
can go.
Before you start to freak out, and say "this is no cheaper than smoking!," please remember you likely smoked from habit; and not as a hobby (chasing clouds, and/or flavor). At least I didn't. All I wanted was a cigarette that didn't taste like the south end of a north-bound cow, and would satisfy my addiction; though your experience may be completely different.
So, to be fair, a "true-er" comparison (vaping to smoking) is probably best to use a low-consumption, unflavored, basic-rig, cost base when you look at "vape" verses "smoke." In that light vaping will always be much, much cheaper than smoking. Everything else boils down to how much do you want to spend for fun and flavor. And how much convenience (ready-made e-liquids, coils, etc.) is worth; compared to time. This can be a no-brainer if you enjoy things like cooking and/or making things with your hands. If you hate doing that kind of stuff, then DIY can become a real chore, and the value of ready-made becomes much more acceptable.
And, of course, none of this addresses the potential savings gained from unknown long-term health benefits.
Bottom line? It all depends on you, and how, and what, you want to accomplish. That is the beauty of vaping in general, and DIY in particular; you can make it what
you want it to be. The hard part is figuring out what you want!