[Kindred]

pawn Код:

CMD:enter(playerid, params[])
{
    if(IsPlayerInRangeOfPoint(playerid, blablabla)) // checks if in range of the /enter point
    {
        SetPlayerPos(playerid, NewPosX, NewPosY, NewPosZ); //Sets there new position
        RemoveBuildingForPlayer(playerid, .....);
        return 1;
    }
    else if(IsPlayerInRangeOfPoint(playerid, blablabla)) // Checks if near the exit door
    {
        SetPlayerPos(playerid, OldPosX, OldPosY, OldPosZ);
    }
    return 1;
}

Like this? BTW, if you are trying to restore the building after it is removed, it is not possible.