Often it makes a lot of sense to spend some money now so you can save more money in the future. Consider filtered water. A high-tech water filter cost about $60 and can filter 7,200 ounces of water. This will save you purchasing two 20-ounce bottle of filtered water every day, each costing $1.15. The filter will need replacing every 6 months. How much will this filter save you in a year’s time?