Because each individual seller gets to set their own prices, this is essentially impossible to answer.
One retailer/audiologist might sell Oticon OPN1 hearing aids for $7500/pair and Starkey Livio AI i2400 hearing aids for $6000/pair. The next guy down the street might reverse that pricing.
So which one is better? The OPN1s for $6000 at store #1 or the Livios for $6000 at store #2?
Well, it turns out that the guy at store #1 doesn't know how to program either pair correctly, so either device is better at store #2 regardless of the price.
I noticed some people say things like Costco. Here is a news flash. There is nothing special about Costco. Any retail store can sell the same basic devices for the same price. And Costco dispensers are just as likely to be poor at programming them as anybody else.
The one drawback to buying at Costco is that you never have the freedom to change your service provider if you suspect they are not doing a good job. Because those devices are locked for Costco. Whereas, if you bought Oticon or Starkey or something else you can probably find another person who can at least verify if your devices are programmed correctly.