As I known, in mont-royal of Montreal, many houses worth over one million are over 100 year old. These houses are very special. Some people told me that the wood flooring in the house is few times thicker that what we have now, and with very beautiful pattern designs, not like ours now, all standard. For sure, the old house need more maintenance. But I don't think the age will depreciate the house value, more important is the condition, location of the house. However, if you don't know much about the construction, some problems could easily bring you out of budget.