I recommend opening the west wing year round as only a 2% occupancy rate would justify doing this. I would hold off on building the pool as it is a major capital expenditure and makes it much riskier that it will breakeven on the investment. Moreover, it is not entirely clear what effect the pool will have on the occupancy rate. Therefore, since it is very likely the hotel can maintain 2% occupancy rates during the off-season, and likely much more than that, this is the best and most profitable choice.