I have felt for some months that the asking price of trumpets was going up.
Here is an analysis of the average prices of 1081 items listed by year.
Note: Sellers on EBay started in 2017 to list trumpets at high prices 'Buy it now' instead of
starting low and letting the auction take place.
To some extent this has eased off in 2018 with auction buyers usually selling their items at sane prices.
But persistent 'Buy it now' sellers find that the item does not sell. A couple have been listed for more than 3 years.
UPDATE Mar 2019:
I am watching 57 ear trumpets on Ebay, 11 are fakes or repro
(there are lots of repros I don't bother with)
Of the remainder,
I would suggest 32 are over priced and have been 'Buy It Now' for months
There are at least 3 that I have offered sane prices on and been turned down and I am not mean.