when is the best time to buy ?

almost every day we buy something whether it's a large ticket item such as an automobile or something as small as a bottle of water, but is there a good time to buy certain items? author mark di vincenzo has just written a new book called buy shoes on wednesday and tweet between 4 and 5pm,  and in the book mark says the best time to visit your doctor for faster service is wednesday,the best time to buy a gym membership is during the summer why? most gyms offer great deals during the summer months to get people inside their gyms instead of enjoying the great  weather outside, the best time to buy a gift card is in January ,the best time to try and lose weight is in the winter, if you like  to tweet the best to  do it is between 4 and 5pm, the best time to buy a pair of shoes online is Wednesday  and for the love birds the best time to get engaged is within a year of dating and lastly the best time to break off an engagement is in the evening and the best time to listen to your favorite radio station 103.1 kiss-FM is all day, OK i admit that's not in the book,but as you can see there is a time for everything , let me know what you  think and feel free to share your lists as well.