With a Large syringe, you can recover that leftover, and now, wasted juice in your spent carts.
I do it now too.
Just pull out the stuffing with a tweezers, from a couple old carts, and put it into a large syringe, then squeeze out the remaining juice.
I squeeze it into a bottle of juice I have, But you have to watch if you use flavors, so you dont mix them, hehe.
If you find that the 36mg gets to high for you, you can always cut it a little with pure water, or a little bit of PG or VG, depending on your preference. I had to cut my 24mg. 36mg I think would burn out every membrane along the way on me, hehe and I was a 2-3 pack a day Marlboro Ultra light smoker.

I have to refill my cart about 4-6 times in a 10-18hour day. I use it sort of like a pacifier too. I use it like a pipe that is always full. I just hit it when ever i think of a real one.
In the past couple weeks, Ive been able to go from 2 packs a day to 1 or less. That means its already paid for the initial kit purchase. $40 = 8 packs here