Buyers on Craigslist who drag out a purchase for weeks and then say something like “can you tell me what size it is?”

No. I can’t. Unfortunately when I wrote the ad containing all of that information the knowledge was transferred directly from my mind to the bits in the interweb. I no longer have access to that information. But YOU do! Just (re)read the ad that you originally replied to and see if the information you need can make the transfer from the bits in the interwebs to your brain.
Good luck!