On what occasions nowadays does one make a Shehecheyanu?
Happy occasions such as birth, Brit, new clothes, new acquisitions, Jewish holidays. When saying the Bracha on purchases they have to be yours, otherwise one makes Hatov Vehametiv. The idea behind the Shehecheyanu bracha is thanking Hashem for something that has happend to one and makes one happy. Rabbi Binyamin Bamberger