Need opinions about fence vs. furnace...?

My husband and I are planning on buying either a fence or a furnace and hot water tank with our tax refund this year. He wants the fence becuase he thinks that when we sell the house, people are going to want a fenced in yard and to know where our property line is. I would like a fence just to keep the dog in (he said no to the invisible fence) but don't think a fence will look good with our house, especially with all of the neighbors other fences around. He wants the new hot water tank and furnace to bring some of our bills down a bit, but doesn't think we need them as badly as the fence. I think that someone would take an open yard and new furnace and hot water tank over a fenced in yard and 15 yr old appliances any day. I guess my question is which will help the resale value more? A fence or new hot water tank and furnace? (Keep in mind we aren't planning on moving for at least 4 more years as well). Thank you!!