The Music Room is Slipping

My experience is totally different. 
You should just sell yourself and see how that works.  
I am totally pleased with TMR

I have had good dealings with TMR, both purchases and trade ins. This whole hobby is overpriced for what you get. Used is the best way to go or direct from the manufacturer. The middle man will cost you a lot, new or used.

Sell on our own, I do thru USAM all the time. Another alternative selling or buying new/used with or without trades is echohifi.com. I’ve been dealing with them for decades. Inventory isn’t as big as TMR but they do carry some good stuff. If you live in the Portland area, go inn and listen to the gear before you buy

I can understand the frustration when selling anything used. I have used TMR and other similar audio resellers plus Amazon and eBay which I classify as generic resellers.

The simple rule is the used value is the price someone will actually pay for a used item, not a percentage of new price (including shipping costs and taxes). For that very reason a number of high end audio retailers I used won’t touch trades or used transactions. It's a totally subjective business.

I have had nothing but reasonable, clearly understood transactions with TMR.  

I was just at their store yesterday. Super nice people.

I sell in other places because they have never offered me a price which worked for me, but they offer a convenience factor which is really a value to many people. 

I buy from TMR, though. That’s an easy call.

Tariffs are likely having an impact on pricing. Not their fault.

Their used gear pricing lately does seem to be getting "too spicy". I've definitely noticed that; it felt like I was seeing much better deals with them in past years. I believe they can command a premium over private sellers, but their prices are creeping over "not worth it" territory for a lot of items - more every day.

This. 

Also, they seem to get a lot of not-very-exciting gear. I think I read somewhere that TMR sells off the runoff of PS Audio's trade program; if that's true, that would explain the surfeit of PS Audio gear and all the lofi stuff like NAD.

And finally, their emails seem to be getting a little too frequent and too "loud", but maybe that's just me.