I believe I understand your request, and I wish I could help out, but I am 1/2 way across the US. As someone who has spent months (and it's an ongoing process that happens every day) documenting every item in my personal collection, I am well aware of the time it takes and the overwhelming nature of putting effort into such a mountainous task. On top of that, there might be emotional issues that come into play when departing with a personal collection. And you have a physical restriction as well as a time constraint. That's a lot coming together against you. I can't be there to help, but here's my advise. (Someone who manages a collection of well over 300 custom keyboards and over 500 sets of keycaps)
The first and maybe most important thing I could think of to help is explaining the current aftermarket scene for this hobby.
The most popular way to do business at the moment is through reddit:
https://www.reddit.com/r/mechmarketSales are fairly safe b/c
known scammers are not allowed to post comments. So, you ask for a comment and chat to verify the buyer is legit. Of course, that doesn't stop a bad actor. But only accepting payments with
PayPal Goods and Services is highly encouraged, and comes with a lot of protections.
The other popular option at the moment is the mechmarket Discord server. I could post a link, but it will expire in a few days. If you're interested, I can DM you a link. There's less policing of bad actors, but you're already limiting to a more discrete set of users. I would still highly suggest you use PayPal for all sales.
This website (Geekhack) doesn't get as much traffic as it did 5 years back. You may find interest here, but the net you cast won't be nearly as wide.
I wouldn't bother with eBay at all. The eBay audience doesn't know the market and you likely won't get a fair resale price for your pieces.
Other thoughts:
It seems you are limited in time and perhaps physical ability to go through your items. But maybe you're overcomplicating it. A spreadsheet is a great start and offers a roadmap for filling in the blanks. Getting started is always the hardest part. Could you sit down one evening and start putting items into a list? I personally use Notion to keep track of all of my keyboard items, but you could just use Excel or a Google spreadsheet. List it all out as you see it or think of it like a big brainstorming session. Get it all out when you can without bothering to fill in details. Save and come back the next day. I find it's best to do this on a platform that is easily usable on mobile as well. That way, if you randomly remember something you have during the work day, you can pull up the spreadsheet/database on your phone and add it. Even if you don't think you could finish this yourself, it will be valuable information for someone who may come along to help you later. As a bonus, if you decide to keep up with the spreadsheet idea, you can make the spreadsheet publicly viewable so that potential buyers can see what you have for sale and if it's available.
I like to keep a list of keyboards and keycaps. The smaller items like accessories don't hold a lot of value to most people. I may note them inside of other items like keyboards (extra PCB, extra Plate, etc)
It could be as simple as this:
Item | Date purchased | Cost | Notes | Images
You'd be surprised how easy it is to track down details for purchases from the last few decades. Email is an incredible tool for finding the missing information. In fact, I don't have a single item of the thousands listed that doesn't have a purchase date and purchase amount. Had to dig through a secondary email account at times, but I found it.
Photos aren't necessary at this point. I think it was best for me to get everything down I could see or think of. Photos came last. Some items still don't have photos. That can come when you list the item for sale. You'll need a timestamp (a photo with your user name for the platform and a date) to prove you actually have the items. (With the exception of discord where you can simply state that interested individuals can DM you for photos). The photos don't have to be perfectly lit or anything. A simple snapshot on your phone should do. Unless you are selling at a premium price, you only need to note/photograph imperfections in items if they detract highly from the original value. Otherwise, you could just state "normal wear and tear."
You can ask for pricing advise on reddit and on here. For instance,
https://www.reddit.com/r/mechmarket/comments/1tt8yqp/official_price_check_thread_month_of_june/Selling through PayPal incurs fees, so you will need to take that into consideration when pricing. Also, shipping is pretty expensive, especially if you need someone to pack the item for you. Again, more to take into consideration. UPS generally wins in my area for cheapest rates for things like keyboards. USPS does have some decent rates for things like keycaps. You can fit most modest size keycap sets into a small priority mail flat rate box and ship for about $13.
I wish you luck and hope you find a home for your collection.
