u/Money-Specialist-997

Hi everyone!
I recently bought my son a second-hand BRIO bundle, and inside was a pretty beat-up box for a Sky Train (33929). From what I can tell, all of the pieces are there and they seem to be in good condition.
After a quick Google, it looks like I may also have the Sky Train Clock Tower (33931) and Loading Station (33926).
I was wondering if anyone could help me with an idea of what these might be worth, and whether it would be better to sell them individually or all together? Or if someone could point me in the direction of somewhere I could get some more information about them.
Thanks in advance! 😊