October 31, 2020 update:
According to CMS, the problems with Medicare planfinder function are fixed. If you decide to switch to a new part D plan, before you make the change, call the phone number at the bottom of the detailed information for the plan that is in planfinder and verify the drug coverage and costs. If you are making a switch by calling Via Benefits or 1-800-MEDICARE, do the same thing. Write down the name of the person you speak to at the insurance company, the time and the date. This way if there is a problem in January you have the ability to contest and change to another plan because of "special circumstances". You do that by calling 1-800-MEDICARE and using the phrase "special circumstances SEP" when you ask to change to another plan.
October 26, 2020 post:
There are, once again, problems with the Medicare planfinder function. The "add a drug" function is incomplete because the drug selection list doesn't have all the drugs covered by Medicare. If a drug is covered, it is no guarantee it will be covered for you if you are using it for an "off label" condition even though your doctor prescribed it. The price stated might not be the price you will pay in 2021.
It is very hard to figure out if all of drugs a user wants are covered by a given plan unless the user goes into deep details on the plan. The most confounding aspect is there is no guidance to tell users that if a drug is not covered, then the cost of that drug does not "count" in the calculations to determine costs for the three drug phases.
Complain, complain, complain to your federal and STATE government representatives. How are seniors supposed to be able to make good choices when they have bad data? Complaining to HHS is a waste of time. Complaining to your drug plan is even more so. Complain to your elected officials. Complaint to your governor, your state and federal representatives, your state attorneys general, and your consumer protection agencies. COMPLAIN