I am not sure where to post it, but there is a new marketplace dedicated to classic phones and smartphones, it is quite cheaper than eg ebay for sellers and is more open and flexible for transactions for buyers, while preserving payment insurance via PayPal.

It is quite new but might be a nice alternative in the future for both sellers and buyers.

(Just to avoid confusion, it is not mine, I just found it and thought that it might be worth a try)

https://market.mylovelyphones.com/