Return Rate % questions?

[fl2000]

Hello,

eBay tracks my returns and calculates a return rate %.

Who is the return rate data for? ebay or is it for my use to identify problem item categories?

Will I get in trouble if the rate gets to a certain level and if so what are those level(s)? Can I get kick off eBay if my return rate gets too high?

Are returns that are considered buyers fault (changed mind etc.) rated different than returns that are considered my fault (not as described etc.)?

How do experienced sellers handle serial returners that bypass blocking by using a spouse or different CC's?

I sell used parts and I currently have a buyer that is trying to repair a machine and he has ordered parts and returned twice to fix his misdiagnosed problem. He just sent me an email that he "thinks" he knows the problem now so he is going to "try" a different part. I am a small volume seller and he is driving my return rate % up.  I quietly blocked him but in the past I have tried this with other buyers and they can just order through their spouse or with a new CC. ( recognized same address). Also, I worry he will get angry when he cannot reorder and leave bad FB.

Should I be worried about my return rate going up? 

Thanks in advance!

[onlinecentral]

Are returns that are considered buyers fault (changed mind etc.) rated different than returns that are considered my fault (not as described etc.)?

These reasons negatively impact metrics.
1) Doesn't work or defective
2) Doesn't match description or photos
3) Wrong item sent
4) Missing parts or pieces
5) Arrived damaged
6) Doesn't seem authentic

These reasons do not impact metrics.
A) Changed mind
B) Doesn't fit
C) Found a lower price
D) Ordered by mistake

[fl2000]

Thank you for the reply

This is the option that bothers me: "Doesn't work or Defective", eBay really needs to change this to simply "Defective".

The buyer sees the first 2 words "Doesn't work" and that can be applied to a part they ordered in error that was not the correct part to fix their problem (buyer misdiagnosed problem). 

Please think about it. "Doesn't Fit" , "Ordered by mistake"  and "Doesn't Work"  are all  interchangeable If they ordered the wrong part. If they choose the 3rd option they get free shipping both ways (and I get the defect).

One nice thing eBay has done that helps this issue is the new return options screen, It hides the "Doesn't Work or defective" down below  in the drop down menu and kind of steers them to "Doesn't Fit" on top. 

I just realized I am not talking to eBay so I guess this is just a rant LOL. I actually tried to talk to someone on eBay today but that option is now gone.