new gPickup[MAX_PLAYERS+MAX_HOUSE+30];
gPickup[pickup] = id+MAX_HOUSE+2000;

public OnPlayerPickupPickup(playerid, pickupid)
{
   if(gPickup[pickupid] >= MAX_HOUSE+200 && gPickup[pickupid] < 2000) //in house
   {
      new houseid = gPickup[pickupid] - MAX_HOUSE;
      printf("Entered house id: %d", houseid);
   }
   return 1;
}