I picked these four bikes up for a song and really need some help with value. I run a bike charity and have a swap meet this weekend. I want to seell these at a fair price. Bike 1 is a Monark Rocket. Cannot find serial numbers Bike 2 is a 65 Columbia with intact tank and front rocket ornament Bike 3 is an MTD Jet Star, no serials Bike 4 is a 1940s? ROAMER Thanks for any help that you can give.