Exactly. Take his advice. To further the argument, if you build your own PC you won't suffer all the bloat ware that comes with every pre-made system, and you can choose the exact specs to your budget instead of suffering losing out on performance because it doesn't fit to what you have to spend.
I think it will depend on the urgency of changing the new computer. If you can wait for more days then am sure it will be worth it. But some times you can visit other online market places and see their rates. You can actually get some good deals.