He gave me a very good solutions to my problems, as did other members on the web...
To me, it's all about condition, but like the forum members that know what the real deal is in respect to the quality and defects of a detector, listen to the them. It became well known that CZ 20's had defected face plates and that the pin point buttons were in the same boat, even the Fisher 5, 6, and 6a had problems with their pin point buttons.
If you are an original owner with the life time guarantee, your alright, but, most of original owners have sold their CZ 20's, so if you buy a used unit, you are at one time or another going to have to up grade to the CZ 21.
If you buy a used CZ 20, you are taking a gamble as to when the unit will need to be up graded when one of the defects kicks in. I bought one, and it looked new, used it once in the water, didn't leak, but the pin pointer got stuck, and I had completely washed her after using it.
Now (if) I would have make a real good find, it would have off set the repairs, and it would have been great. But, to have to send in the CZ 20 thinking it was going to cost only 185.00 plus tax a like couple of years ago, and not be able to repair it because I just did not have the money. So I stored it in the closet, took out the batteries, wrapped in plastic.
Decided to water hunt again, and the repair price went to 299.00 and was not happy, not only did I did not have the funds to repair the CZ 20 again. So this summer, I bought a used CZ 20 at a little more of what it would have cost to repair the 20 I had, but, it's a gamble, and I made the wrong decision, and was able to go on a couple of hunts in the water, and again, my finds were nothing to write home about. Now, this 20 I made sure that I had sealed it correctly, and the battery compartment still leaked, but no water in the upper housing, so that was good. I plan to up grade both 20's and sell them off at very little lost, as the beach season here is over, and to leave an up graded CZ 21 detector in the closet, to me, is very unproductive. So, if you purchase a used CZ 20, even it it's working, get the best price you can and send it in for the up grade, especially if it's fall or winter and you hunt the north east. HH...
Philo