If it’s a stock anthem I’d probably just put the whole bike up for sale, here/pinkbike and then ebay as a last resort. If you have decent kit on there that folks might want then split. Check the classifieds for what is selling and for what kind of prices.
As above, also consider postage costs, ebay, and paypal fees. Postage is eye wateringly expensive depending who you send with and at what cover. It cost me over £15 to send a kids balance bike last week via PW48 but I couldn’t justify charging someone that so lost a couple of quid.
If you can get someone to collect then cheaper all round and the buyer can inspect first. If you have to use ebay/paypal then you can kiss goodbye to at least 10% of the sale price, although things seem to go for silly money on there at the moment so that might be covered.
Oh, and splitting can be a pain in the arse as you’re constantly going to the post office (or in my case the wife is!).