domain name value

Hi, im have some domain names in reserve ( not yet reistered ) but im not sure about the value. Does anyone knows a good site for domain name valuation ? I found some commercial sites, that charge you for they service but this would cost me a lot money. Thanks in advance.

Hey Guys, just wanted to see if my domain maybe is worth something if i tried to sell it here's the domain name: rentappartments.online and any suggestions on where to sell it would be much appreciated for the moderators if this is the wrong section for the thread please move it, thanks!