I am sure this is going to make it tougher to get my own keys, but too many people seem to be struggling getting the hard to find keys, and I have a method that works very well, so mine as well share.
have at least 500K and ideally 1M Rubles ready to spend.
go into the flea market, show barters, and find all the keys you are looking for. identify them and right-click and add them to your w-list. ideally, aim for 2-3 keys at once so you aren't wasting time.
go to your w-list, and turn back on "remove barters". now continuously refresh and then click through all the keys while waiting for the refresh counter to expire.
Rinse and repeat until one flashes up for sale for rubles. for me, I have gotten every key I needed this wipe in under 10 minutes each. Throw on some background entertainment and grind them out.
This wipe, I used this method to successfully get blue tape key (100k), both Reserve medical building keys (500k each), Radar (700k), operating room (200k), and cottage (300k).
Good luck!
Source: https://www.reddit.com/r/EscapefromTarkov/comments/whj9o1/how_to_get_hard_to_find_quest_keys/
