Welcome Angi,
I did not see anyone answer your questions, so I will try. These questions have been hashed and rehashed on this list a few times , but since you have no way to know that without reading the entire archives here goes. Any time you place a letterbox on private property you should ask first. It is against National Park Policy to place a letterbox in a National Park or Monument without prior approval and I doubt you can gain approval in most situations. Generally speaking it would be fair game to place a letterbox in the National Forest,BLM areas, city parks, county or state property, but in some cases there may be specific rules to preclude leaving items. I generally feel that it is easier to apologize than to ask permission, so sometimes I will do opposite of the above , but can not recommend violating some guide lines. You should be aware that if you plant a letterbox and post clues then that letterbox can be located by using other search engines other than the LBNA site. For example if the title to your letterbox is"XYZ Letterbox" you could go to Google and find the letterbox clues by searching for "XYZ". This would or could pose a problem for the letterbox if you planted it on XYZ private property or XYZ National Park without approval. In most cases park officials(other than NPS) tend to ignore letterboxing ,but nature centers, preserves, wild life areas get concerned about habitat destruction. I hope this answers your questions. If there are no letterboxers in your area the time worn phrase is "Plant them and they will come". It works!
Don

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