There are numerous synonyms for the phrase "buy it" which means to purchase something. Some of the common synonyms are acquiring, procuring, obtaining, getting, securing, and purchasing. You may also use words like investing or splurging when you are talking about a more significant purchase. Other possible synonyms include picking up, taking ownership, and grabbing. However, some of these synonyms have specific connotations. For example, "acquiring" sounds more formal and usually refers to obtaining something valuable or rare. "Grabbing" is more casual and may imply impulsiveness. In summary, there are many words you can use instead of "buy it" depending on the specific context and your desired tone.