The threads for this pattern is not DMC. It is Gentle Art floss. So the price is different for each of them.
The DMC is more cheaper and it was in the market since 250 years ago. But the Gentle Art is a new brand name in the market. Good luck.

Is there a big difference or will the DMC work?

Gentle Arts floss is "overdyed" floss, made in smaller batches and often slightly variegated to make the colors blend beautifully. If you don't want to spend that kind of money, you can find a conversion chart via the internet and change colors to DMC floss, whicb is a big savings. However, some of the colors will look quite different. I wouls wait until I got the pattern and be able to perhaps puck just the unvariegated colors to save some. The black I know is DMC #310, which is called Wrought Iron by Gentle Arts. If you just search/google for gentle arts to dmc conversion chart, you will find several available. The lighter pink heart loks variegated to me.

I am nit annemployee of ECS, but another sticher on this chat group hosted by ECS.

Thank all who responded. Nice site to get a ? answered.

Nice to have you here! You are welcome to join this chat anytime you choose! You can just hover or chime in! We enjoy helping our fellow stitchers. You can imagine my joy and my financial dismay to find all the newer stuff available, as when I began stitching, there was linen, which I can no longer can see, or black or white aida (black was hard to find). No internet, no colors but many generations of stitchers using DMC or Anchor floss.

I really must do something about my Delusiin of Inexhaustible Fnancil Resources!