Your Colt is an "Official Police" model - that was just Colt's name for it, and does not mean they were all police guns. The Official Police was the medium sized Colt revolver, bigger than the Police Positive and smaller than the New Service. It was a bit bigger than the comparable Smith & Wesson, and its frame and mechanism were the basis for the later Colt Python in 357 Magnum.
Your general version of the Official Police was made from the 1920's to the 1960's. Based on the front sight and the "Coltwood" plastic grips, I would say yours was made in the first few years after 1945. Colt did not use the plastic grips on guns for the civilian market for very long - they came to be seen as "cheap" rather than "modern". I think they may add value to your gun because they are somewhat scarce.
I'm afraid I can't suggest a value for it. The finish is somewhat beat up, which makes it less appealing to Colt collectors.
There is a Colt Collectors Forum:
but I have never posted there.
Your Charter Arms revolver looks quite minty, and judging from posts in this forum, collector interest in Charter guns - especially the early production guns - is increasing. Charter Arms ran into financial problems and quality dropped as time went on, but the early guns are well thought of.
I realize the above does not answer your question, but I hope it helps. It is easy to find gun auction websites (the firearm equivalents of Ebay) with a quick Google search, and you may be able to find sale prices for similar guns that way.
PS - Thanks for putting up photos! Other people here should be able to give you a more direct answer because of that.