I've been fairly concerned that some of the Johnson County parks are prohibited. It might be just a selected few.
I have been pretty much exclusively a park hunter for the last year, (found a ton of clad, some silver dimes and a bunch of silver and gold jewelry), and here are some rules for the area around me.
http://www.mwas.org/forum/index.php?topic=2710.0
JOCO parks you need a $6 permit which is good till 12-31...other permits are free online.
I buy mine at Shawnee Mission park every year.
Other cities have their own rules, most are open, some are not.
Prarie Villiage, for instance, you can scan all you want...you just can't dig holes of any kind which kind of defeats the purpose and is very frustrating so I just hunt other areas.
On the MO side you have Loose, Penn Valley and Swope, among many others.
Lake of the Woods picnic area and bike trail is off limits in Swope, but our club has hunted there twice on Sunday meetings this past summer because one of our members knows the head ranger and got us permission.
Lots of great targets were found on both hunts, our July hunt was written up in the Sunday paper with a great positive article and pictures.
The thread in the link says Clay co. is off limits, but if you call them this seems to be not true.
All holes should be clean and as undetectable as you can make them, which is pretty easy in this great dirt we have around here.
