Here’s an easy explanation. The cheaper Serato devices are usually “upgradable for SDJ as purchase via a license” The more expensive hardware devices are usually “plug n play” compatible with SDJ which means they don’t necessarily require a license the product itself unlocks the pro features of the software. When you purchase a SDJ license you unlock any and all hardware that is compatible. For example if you purchase a Pioneer DDJSB3 that product will now be fully compatible with SDJ Pro due to your license. However you can pay the full $129 for the license or do a monthly paid subscription to use SDJ Pro. The choice is yours

If you’d rather subscribe for $10 month here’s the link. When you subscribe you get all the expansion packs unlocked as well like Serato Video, Flip, pitch n time etc. If you purchase the full software license you do not get all the expansion packs with it. Hope that helps serato.com

I don't want to pay monthly.... I want to purchace one time only!

Then go to the Serato store and purchase it

So there is no discount at all?!!

No sorry. They have discounts or half off every now & then which they announce on their social media but it is not discounted at the moment which is why i suggested the $10 month subscription for you. Or you could just use SDJ Lite their limited software which is free. You can also do a free trial of SDJ Pro just download it 👍🏼

Free for 14 days. Knock yourself out👍🏼
serato.com

OK Thanks! I will use the Lite version, since i find a discount.

Why do you automatically expect you should be getting a discount anyway?