In Oregon by law we have to post our paperwork at the growsite. Some people post them on the doors. I am like SM and do not agree with doing that. I keep all my paperwork in a folder close to the grow room.
First of all if the PoPo's are IN your house in the first place you are fuct to begin with. Do not let them in unless they have a warrant. It is not show and tell if they ask, its show me the warrant is what I ask.
Also the outdoor growers here copy there paperwork and put it in plastic and stick it to there outdoor spot. They keep the origanls inside. It is still proof enough. The leo here is supposed to call DHS if there is a suspected grow. If there is paperwork then they leave it alone, unless it is a outdoor spot, then they count the plants, call in DHs and see how many patients they are growing for. If it all adds up correct they do nothing. But if you are over then they come knocking. Some are cool and if you are over, they will just take that plant or just have you cut it down right there, also they still have a few years if they decided to come back and charge you on it. This has happend to a friend of mine when they thought they had all the paperwork in.