You just did the same search, about 1 minute apart, on Expedia to find a hotel with the same dates, the same number of occupants and filter both in a window where I would I am connected to Expedia and an Incognito Chromium system and got extremely different results for many properties.
The price once connected is almost triple! It's the same room, of which it remains 3, and they even give an extra day to cancel with the cheapest price. This allows me to buy directly without logging in, so that the lowest price is maintained.
This is one of the most important differences, but at times the price recorded was slightly lower than incognito, so that going incognito does not seem to guarantee the best price. Maybe there are other prizes as well, depending on sponsorship links, ads, and so on. (There is an office supply store that offers a discount of almost 30% when airing an ad, but in this case it is still consistent).
Note that the address is the same but the phone number is different. Probably so that the agents know what level of pricing the callers come from.
How can you ask Expedia to quote its best price for hotels?