Bill,
I'm sure you'll find a rig that suits your needs / your application...at whatever your budget is.
But, if you don't mind, I'd like to help you (and others) a bit here, with some polite clarifications?
Not the least of which, you'll need to define
your specific needs / applications (no need to tell me....but you should detail these for yourself, before
you spend
your $$$$) and then look for a radio that meets those needs.
(of course, we just got done discussing the old 90/10 or 80/20 rule....where you should spend 80% - 90% of your ham budget on "antennas", antenna system, etc....and only 10% - 20% on the radio....so, I'll not ramble on about that here! If you care to delve into all of that, have a look...see some links below for details on these...)1) So,...We all know the
"value" of anything is what someone (or many someone's ?) is willing to pay for it....or what they are willing to part with, in order to acquire it....
So, if the price being asked is higher than you think it should be, you can always offer less....you just never know, maybe you'll pick up a good rig for a good price.

And, while generically, I agree that
some older rigs are overpriced....but, some are damned
bargains! It just depends on what rigs, how "old" is old, and what condition the rig is in!

I looked at a Yaesu FT-1000 MP rig online and the gentleman wants $1150 for it.
That seems high to me as the radio is 20 years old or more... right?
And, I doubt Yaesu will even service it anymore so if something goes wrong...
<snip>
Anyway, I guess I'm going new radio unless I run into a reasonably priced radio in good working order. I mean, why not?
I'm just trying to understand this crazy pricing of used equipment.
2) Now, in this case....the old venerable FT-1000MP was a top-of-the-line rig, and in it's day (and still, even today) was a much loved and respected rig....and back 20+ years ago commanded a rather steep retail price new.
The original FT-1000MP came out in late '95 (?), and depending on how equipped, was priced (MSRP) from $3600 to $4200 (most were fully tricked-out at $4200 MSRP.....with a street price of ~ $3500, in 1996, which in today's 2022 dollars would be a street price of ~ $6600.)
Now, if this particular FT-1000MP that you're referring to is the FT-1000MP MkV (very well respected and quite sought after radio), in the year 2000 it had a MSRP of $4200, and a "street price" of ~ $3400 - $3500....which in today's 2022 dollars would be a street price of ~ $5900 - $6000.....and, since it is not only a rarer radio, it also holds it own quite well on-the-air, it does command a rather high used price.
So, asking $1150 is not really "asking retail", it's actually fairly reasonable (in my opinion, maybe a bit on the "high end" of reasonable, but still not "current retail")....unless you're trying to compare apples to oranges and/or trying to base the value of a ~ 20 year old top-of-the-line radio, on what the current entry-level rig costs along with its expected depreciation over the next 20 some years, 'cuz then you might think that a ~ 20 year old radio should be worth what?
$1150 is about one-third of the actual original dollar price....but is < 20% of the original price times the inflation....so, what is a reasonable value versus new?
Ah, that's the $64,000 question isn't it?
And, here we come back to the original premise ---- that the value of something is actually based on what someone is willing to pay for it, yes?
Perhaps download and read the ARRL Product Reviews of these rigs, and then do the same for some of the more "modern" rigs that might strike your fancy.....(then, if you have extra time, do the same, looking at eham reviews, etc....but take them with many grains of salt!)
And, you might see that there is not only a lot of life left in some of these older rigs, but also they might just perform better than many similarly-priced new "modern" radios.
{first things that comes to mind are the crappy ALC systems in some "modern" rigs....of course, there is always the "watery" DSP NR, etc...and in many cases, sometimes useless noise blankers, etc. of some "modern" rigs compared to some "classics"...of course, anyone out in the country with neighbors with electric fences will gladly trade one of the "modern" rigs with rec AGC issues (AGC activating on the noise pulses of the electric fence chargers) for a 20+ year old FT-1000MP!, in a heart beat...}
Just reminding everyone that while "new", "modern", "high-tech", DSP, SDR, etc. are nice in some cases....in other cases they aren't what gets the job done...
3) While I personally am not interested in a '1000MP....but a MkV would be nice (and, if I found a nice clean one at a low enough price, I'd snap it up in a second).....and, while would not pay ~ > $1100 for a MkV, some would do so....and, hence the reason that some are asking what they are.
And, since there are fewer and fewer rigs with Class A transmitters still alive and working well, I suspect that MkV's will actually start going up in price (appreciate a bit).....[I could be completely wrong about this last comment....just me rambling...]
4) Finally, Bill (K4BDA) I might be reading too much into your posting / query here (if so, just ignore this last point of mine here), but I seem to infer a somewhat negative impression you have for a "radio is 20 years old or more"?
If so, I'm wondering what application you may have that an FT-1000MP is unsuited for?
(I suppose if you were a serious 160m CW contester, you'd want a better receiver....but, that's gonna' cost you more than $1100, too...)
And, further, while some older radios do have some issues as they age...I'd take a 20+ year old FT-1000MP MkV (even at ~ $1100) any day of the week over some of the "modern" HF rigs on the market today...and, there are many folks out there that can service a '1000MP much better than Yaesu.

{heck, there are some of today's radios that I wouldn't take if you gave them to me, for free....but, that's a whole 'nother discussion....

}
Anyway, I do hope my pointing out the performance of the ole' venerable '1000MP (and the better performance of the '1000MP MkV, along with its Class A transmit capability), and the costs of these radios, etc., helps you out.....
But, perhaps the most important thing I'd like to highlight is that like in many areas of life ---- doing the homework / research (look at the scientific product reviews, etc....and understand what the specs the manufacturer and reviewer are quoting, actually mean) is pretty darn important!
'Cuz there is a lot more to this (an FT-1000MP) than just a 20+ year old radio.

Maybe just have a read through of the discussion here on "Station Building"....there is a LOT here, but many have learned a lot from it:
https://www.eham.net/community/smf/index.php/topic,128776.msg1194749.html#msg1194749https://www.eham.net/community/smf/index.php/topic,128776.msg1195427.html#msg1195427https://www.eham.net/community/smf/index.php/topic,128776.msg1227431.html#msg1227431https://www.eham.net/community/smf/index.php/topic,128776.msg1221132.html#msg1221132https://www.eham.net/community/smf/index.php/topic,128776.msg1275560.html#msg1275560And, if looking for some more discussion on HF Radio Suggestions....have a look here:
https://forums.qrz.com/index.php?threads/hf-radio-suggestions.839022/#post-6366728https://forums.qrz.com/index.php?threads/hf-radio-suggestions.839022/page-3#post-6367308https://forums.qrz.com/index.php?threads/hf-radio-suggestions.839022/page-3#post-6367343https://forums.qrz.com/index.php?threads/hf-radio-suggestions.839022/page-6#post-6378709https://forums.qrz.com/index.php?threads/hf-radio-suggestions.839022/page-6#post-637821973,
John, KA4WJA