I've found the rules to be a bit opaque... but from what I've been able to tell, placing an ad for a 3rd party fulfillment site like Zazzle probably violates Nextdoor policies... I'd be happy to have someone tell me otherwise, but they do list these among the things that are not allowed...
- Listing items that you are selling for a business, including resellers, and commercial consignment and estate sellers.
- Listing items as part of an incentive sales program, for example, Mary Kay Cosmetics, Amway, Avon, Scentsy, etc.
https://help.nextdoor.com/s/article/Best-practices-For-Sale-Free?language=en_US
I've felt OK linking to individual products occasionally, when the product specifically addresses the topic of discussion, like back when people where searching for where to buy masks, but actually placing a listing in the sale/free section or as a post I think is not really allowed.
