There is an interesting thread that is getting a lot of attention about the cost of brand name guitars. There was one comment made in it about one's passing away and the wife and kids deciding to sell everything.
 
Myself, I have created a listing of my guitars and other musical items that I feel have value, and included an approximated dollar value for each to use as a guideline.  Granted, these are just estimations and the market at the time would reflect the actually or not. The real point here is that my wife knows nothing about the value of some of my gear. I expressed to her that I did not want her selling this stuff at garage sale prices. Yes, she would be making some musician especially happy walking away with a Fender Strat for $50.00. But I don't want that to happen. She could use the money and is justified in receiving it. My instructions also included working with a relative who does know musical gear values and he could get a commission or something.
 
Just thought I would mention this. Granted, this it is not something we want to think about, but I would hate the thought of your family giving away potential 'gold'. 
 
...Ken

Just make her aware of these publications and instruct her to seek out the latest edition when the time comes...
 
http://www.amazon.com/Blue-Book-Electric-Guitars-Edition/dp/1936120178/ref=pd_sim_b_1
 
http://www.amazon.com/The-Blue-Book-Acoustic-Guitars/dp/193612016X/ref=pd_sim_b_2
 
And I guess this one is for more vintage type stuff...
 
http://www.amazon.com/Official-Vintage-Guitar-Magazine-Price/dp/1884883230/ref=pd_bxgy_b_img_y
 
Another thing to do would be to make sure you leave a detailed list of exact year and model of each guitar as well as details in regards to alterations and not so obvious imperfections. Then she could look around on line to see what people are selling similar guits for because sometimes Blue Book values don't necessarily reflect what the market will bear.
 
Cheers.

You can't sell stuff without a buyer.
 
The buyer usually tells you how much it is worth to them.
 
I think it is a waste of time making extensive preparations to prove something has value, although I think a simple note with a ball park guess would be a kind gesture.
 
If you think it's worth more than what it's worth... sell the darn thing now and avoid belaboring your survivors with the responsibility to get top dollar.
 
best regards,
mike

Take them with you...  It worked for the pharoes!

I think the point was more about not letting something that's worth a couple grand go for a few hundred. It can be very difficult to tell for even people somewhat familiar with guitars. For example... an old 70s special edition strat in mint condition gets mistaken for a more recent standard model. That can be a serious price difference. Also certain instruments can occasionally become valuable in a given year for whatever fickle reasons. Knowledge is power and the family member can make an informed decision as to whether they want to unload it quickly for a reduced price or don't mind hanging on to it for a while waiting for the right buyer. Lots of unscrupulous dudes out there who would take advantage of guitarist's widow and I would certainly not want one of those jerks getting away with it... especially if she needed the money.
 
Just sayin'.

And let's not forget we don't always get any warning as to when we are going to depart this rock. Best to have affairs in order to be safe.
 

I thought about having an affair once, but I thought it safer not to..

Yeah, my wife would kill me and sell all the guitars.
 
:-)

My two best buds are both fab guitarists and collectors and we've agreed to "curate" whoever goes first's (and second) collection for their families.  Plus they've both got sons who are players and enthusiasts who already know as much or more as we do.  And I have mine insured so there's always a current detailed list of valuations.