I did that several years ago, when I thought I would never be able to sew again, and like you was moving.
Here's what worked for me ....
I did NOT want a public garage sale, as I was letting people into my home.
I sent emails out to everyone on my email list, telling of the quilting/crafting sale items, indoor, date, hours, etc.
The email did say it was fine to pass it on to other people who may be interested.
I washed all fabric, and tagged it with the measurement.
No pressing, just a simple fold up, so they could all be laid on a table.
To make it simple for everyone, the price was set at one price per yard.
To get into different rates for different fabrics complicates it for everyone.
It was easy to add up the total yardage and then multiply by X.
Likewise for patterns and books.
I kept my price consistent for all things of the same type.
And yes, not everything falls into a group, then it gets a different price.
As for what price? ... you have to do what is best for you.
Do you want to be rid of it all? ... or content to downsize and just have less?
As a final thought ... be sure to hold back some of your favourites, so you aren't later saying, I wish I had ..........!!!!
Good Luck!!!!!!