Only Allow Bids from Authenticated Members

You can't do this within My Products, but you can if you export your products from MP, edit in spreadsheet, then re-import.

I could do that in about 2 mins.

See the guide here..

CSV Export - edit - import - Bulk update. How to guide. – Help - Trade Me

I know Gary has given you a good answer, but for an idea outside the box why restrict yourself to only some buyers?

I ran some tests a few years back and there was NO MATERIAL DIFFERENCE in the rates of failed trades whether a buyer was authenticated or not. 

I'd just leave it unticked, then monitor sales and fails. You might decide it's better to leave it unticked. 

Even if it was a heavy factor in fails, the maths just doesn't stack up.

This is super simplified but imagine:

Option 1. Unticked: Item in front of 100 people. 50 sales. 2 fails Total profit $48

Option 2. Ticked: Item in front of 50 people. 25 sales. 0 fail Total profit $25

Thank you

I just had a few $1 Reserve auctions this week - it tends to attract difficult customers.  All good, thanks for your feedback :)

silkbutterfly

    Yes, it is the new Buyers that cause most problems, un authenticated/New accounts to are often time wasters, Blacklisted members who create new accounts to circumnavigate Blacklist, as using same credit cards to authenticate can link accounts so do not authenticate, as do underage people / teenagers, yes for low cost items, they are sometimes problematic,

few years back I had new buyers that were 100% scammers, buy Now on one $1 reserve and want to drive a 3 hour round trip from location to pick up a .50c or $1 plastic block, no communication at all from them, I contacted Trade Me and account goes poof quickly, this happened many times, Another reason I stopped pick up's years ago, start of Covid, So I do not have to give out my address and no need to give phone number out, 

This is why we use to tell people do not put that stuff in Automatic Payments details, scammers are looking for information,

Early this year I got Payment instructions from a seller with all the information I needed to go and open up fake accounts etc. at shops or what ever, so dam stupid, I have never ever even given my full name out for bank deposits, only ever been a partial match, Initials only, my Trade Me E-Mails do not have my name on them either, People need to wake up about information they are giving out these days to strangers, people they do not even know, The world is changing,

I do not have buy now's anymore, so make Manual Fixed Price offers, and the amount of new accounts not authenticated, and watching, could probably linked back to Blacklisted members, so I blacklist them, if they have been blacklisted it is for a good reason, a lot of those new accounts blacklisted still have no feedback & not yet authenticated?, one is at -1,

and this is another reason I have stopped buy now's it is just too easy for members to create fake accounts and Authenticate with $1, it needs to back to $10 like it was many years ago, people may think twice about creating fake accounts as $10 is too much to lose if account gets closed,