I’m not going to try and talk you out of moving on from Costco, since you have audis nearby and Costco is now several hundred miles away. But some expectations-adjustment may be helpful.
As Consumer Reports suggests, there may not be much difference between brands in terms of reliability. Costco’s aids are built by other companies and are not less reliable generally to aids sold by others, as reported to CR by users. As you’ve discovered, eyeglasses may be termed plug-n-play where hearing aids are more plug-n-pray. Not that a miracle is needed, but aids need a lot more ongoing attention than eyeglasses.
Today’s digital hearing aids have very limited life expectancy. Even with the cleanings and adjustment, in my experience, the mean average life expectancy is about five years before replacement will likely be needed, so that’s part of the reason yours may be feeling over-the-hump to you. Three year-old aids often start needing repairs such as new receivers. Some people get a few more years beyond five. Others get fewer. Audis don’t tell you that when you’re shopping.
So if you do move to a private audiologist, have a price point in mind that makes sense to you within that five-year timeframe. I personally wouldn’t go top-of-the-line for just this reason; it may still only last five years with no better bang-for-the-buck in terms of reliability, but if your budget’s not as price sensitive and the top-line tech makes sense to you, you can do that. The higher price of top-line models reflects newer technology more than better reliability, generally speaking.
Not every hearing aid needs wax guards. Many receiver-in-the-ear (RITE) models or variants do; many BTE aids do not, because wax is unlikely to get up to the receiver, if you clean your tubes and domes every night or as needed, but BTE’s may need tubes and domes changed every few months. (These are cheap.)
Even with wax guards if you have aids that benefit from them, yes, you do need cleaning and adjustments, but there’s one other thing I didn’t see you mention that can reduce the need for repairs: use an electric hearing aid dehumidifier/dryer every night. It might add a year to hearing aid expectancy and reduce the need for new receivers. Some audis include them bundled with new aids because it saves them work. If not they’re available in the $50-$100 range as at amazon.
Good luck. Happy shopping.