Original 1963 list price around $1750 (about $11,500 in 1996 dollars).
1963-1982 history unknown.
1982 - Friend purchased trailer for $350 in 1982 (about $730 in 1996 dollars).
1990 - Friend gave me Yellowstone for free. Bad suspension (leaned to one side).
1990 -1995 Trailer used as storage shed.
1995 - Got the "bright idea" to use trailer as an operating station for Ham Radio Field Day.  Jacked the trailer out of the mud, and replaced the tires.  Ran "temporary" (still there) wiring to tail  lights.  Rebuilt bayonet sockets so lights would work.  Replaced missing marker light. Repaired frozen septic valve.  Towed trailer to mechanic.  He repaired (welded) suspension and repacked bearings.  Everything basically functions except LP gas fridge. Wife made new curtains.
1995 - Present - Trailer used for Field Day and camping (short, local, trips) every year.
1996 - Added Shademaker awning/screen room. Added under counter clock radio and TV

2001 Field Day (not me, another operator)

2005 - Septic dump valve broke.  Non-standard "water faucet style" brass gate valve.  Plumber replaced with brass ball valve (ouch $$$).
2006 - Removed 120/12V lamp over dining table (60W bulb had left burn in ceiling).  Installed decorative bezel to cover burn.  Installed new light with 2 35W compact fluorescent bulbs (more light and much cooler).  Still using original "retro" shade.  Purchased NOS exact replacement tail lights off eBay (not yet installed).
2007 - Sanded, primed, and painted frame (black) where exposed and badly rusted (rear bumper and front hitch area).  Had new Tekonsha P3 brake controller and 7 way connector Installed on tow vehicle (95 Nissan Quest).  Installed a new 7 Wire molded cord Hoppy 20146 on trailer to replace the 4 wire system.  Installed federally mandated break-away brake activation system. This was the worst "kit" I have ever installed - basically, it was  a box of loose parts. Add your own wiring and lugs per schematic.  Old brakes still worked after 15 years of not being used. Installed new Equal-i-zer LD hitch 90-00-0600 with integral anti-sway.  Could not use hitch for the TCT trip in May because shank was too deep for Quest factory receiver.  I later had 1/4" of solid 2" x 2 " steel cut off.

Future Projects - Would also like to spruce up trailer with a coat of paint (trailer was brush painted sometime in the distant past (yuck).  Also, inside wood under rear window needs replacement (water damage).  Would like to figure out some way to add Air Conditioning.