@kaskonauta wanted to buy a Maths 2013 from me (230 euros w/o shipping and PP fee)
He later offered to buy along the Maths an Optomix V2 (180 euros w/o shipping and PP fee)
I proposed a price for the package : 400 euros including shipping (12 euros) but w/o PP fee. Turned out 397 at last (minus shipping). The parcel is sent. @kaskonauta also manifests an interest in my Erbe-Verb.

"Hi the package has arrived. Everything works. Thank you!
PS: Did you sell the Make Noise Erbe-Verb?"
@kaskonauta left a positive feedback on my account.

2 weeks later, "There is a problem with the mixer's center knob number 3 ... Why didn't you inform me?"
"I've never had this problem and would have told you (in fact, I would not have sell it at all) ...
You can try and have it cleaned up and i ll refund you . If you want to have it sent back to me, we can discuss about it, no problem ...
I think you will understand I will not make 25 euros off the Optomix alone (180) including shipping (12).
I received 397, so will refund you up to 205 once the module is back."

@kaskonauta does not agree on the price.
Paypal dispute (my first one) : @kaskonauta pretends the Optomix is also faulty.
@kaskonauta loses his dispute.

He now keeps flooding me with paypal payment requests or comments on my youtube channel.

The knob on Maths can be cracky (never witnessed that though), that's why i offered paying a cleanup or refunding.
@kaskonauta wanted to keep the discount price and refused both solutions.
As said previously, he lied during the Paypal dispute in order to obtain a full refund which was a bit too much for me and probably helped him lose the case. He later justified that : "I don't know if also the Make Noise Optomix is in fully working condition, because I don't trust you anymore."