Recently I heard Towny PVP is disabled on survival. Personally I don't see the point in this and that's why I would like to suggest to give town owners the ability again to choose which plots in their town have PVP enabled. Before entering a PVP area there are clear signs with rules and information. Players who enter the PVP area know (by reading the signs) the terms and conditions. One of the things written on it is that players will not get refunded when they lose items. Quite simple since you enter a PVP area. Besides the explanation on the signs it is not allowed to tp players into a PVP are without them knowing. When players do this they can be reported and they will be punished. The points stated above applied to the survival server before the reset. There were no problems at with these rules. A lot of players like making small (or big) PVP arenas for survival. They like to PVP sometimes without going to a different server.
Unless you make rules or agree on giving back the items you lost. If you do this, make sure you have a screenshot of the agreement or something. I'm not sure if staff can give items back if you agreed or talk to the person who 'stole' it from you.
