DS who's 21 is looking to upgrade his phone and buy a newer version, he currently has an I Phone 7 and has had his current one for 3 years. Whenever DS is looking to buy a new technological device DH will offer his assistance in looking online for a second hand phone which are still in very good condition and like brand new. The one DS is wanting to buy is around £500- £600 and off amazon and brand new, DH has advised DS he thinks it's a waste of money and too expensive as he's only a student and not earning an income. I think DH intentions is just to offer his opinion but I think DS thinks DH is being a bit interfering and he doesn't need help to buy a phone at 21.