I was one of the few who voted no prerequisites on auctions. Given the other options, and due to my own personal opinions, it seemed the best choice to me.
Looking at the options that include prerequisites, my thoughts are as follows:
A week old account - this is pretty much nothing and in my opinion, provides very little benefit. There may be a few scammers who are in a hurry and don't want to hang around, but a week is not long and is not difficult to avoid. Literally it's just time and is easy to acquire. If a scammer wants to scam by hosting a quick auction, it would simply require them to wait a week and then go about their business. However, I am hesitant to suggest a longer time frame... While in my opinion, a longer waiting period would possibly be more discouraging for a scammer, it again is not difficult to wait out and it also has the risk of turning off actual potential participants. Generally, if someone is holding an auction, I imagine they want the largest audience possible, but perhaps I'm off base in that assumption.
Five feedback - this may be the best option out of all of them in my opinion, but is still kind of meh. What if someone is only selling a RR or other toy they wish to auction? Possibly slim, but could happen. I also do not think feedback is widely used, and not everyone sells things only on DM. What about someone who has multiple positive experiences elsewhere?
Ten comments - like waiting a week, comments are easy to make. Will they be required to be medium or high effort? If so, what does that look like and who decides? This, in my opinion, is not a good demonstration that someone should be trusted.
Five vouches - My question with this one is where will these vouches be requested? I've been in this community long enough to see drama... People who dislike each other... This could work, but also could be extra drama. Maybe I'm jaded and cynical. I also wonder about those who are not scammers but who may be new, shy, too busy / no desire to participate in the community / etc. What if they would like to participate but for whatever non nefarious reason don't have anyone to vouch for them?
I think that's the reason reddit was so popular to sell on was because it's easy and quick, doesn't take a lot to get started, there's not lots of rules you have to learn / follow, and you don't have to use it for anything else if you don't want to. Anyone can start at any time.
I understand the desire to protect those who are already here, but when I think about other suggestions for what I think would be fair and a better option, I can't think of any because my answer is still no prerequisites. We're all adults here. We should all be educated about how to use PayPal to keep ourselves safe. Buying / selling online will always be a risk and I'm of the opinion that people shouldn't be treated like scammers until they give a reason to be treated that way.
I'm not a scammer and having so many rules is a turn off for me. I've seen similar rules on other forums and multiple times it's prevented me from participating. Maybe I'm the only one who feels that way, but I think these would all provide a false sense of security. A scammer can still scam if that's really what they want to do. I guess I prefer more freedom, even if it requires more responsibility from myself to be more vigilant.
After I've written all this, I just realized... Is the rule that requires proof of every bid still in effect? If that's the case, everything I just wrote may be pointless in regards to my own participation as I find that rule an invasion of participant's privacy and is exactly the kind of micromanagement I'm not a fan of. I also dislike the rule of limiting auctions only to DM. Again, narrows one's audience and is unnecessarily accusatory. But perhaps now I'm off topic...
So, just to clarify something: how would you track that someone has been vouched for?