Just watching Antiques Roadshow and there's a lady getting her Dad's logbook appraised - Bomber Command - shot down over Hamburg in 1942 and ended up in Stalag Luft VIA and escaped from the Lamsdorff Death March! No idea how old this episode is. Kept a diary in April 1945 while he was in hiding. He was with 106 Sqn. The appraiser just said it's not worth a lot of money but...oh the history!
Unfortunately AR don't have a proper idea of a lot of such stuff, except medals. I've seen a couple of logbooks and have been screaming at the screen as they give their estimates.