The 2020 Trek Checkpoint SL6 has a MSRP of $3800 and currently bike blue book has a value of about $2500.
Bike blue book was severely undervalued pre pandemic for my market (priced too low on BBB) for bikes under $1000. Things are different now. I'd suggest trying to list it between $2700-$3000 and see what happens as every market is different.