You would do A LOT better buying parts and putting one together. It is not difficult. You can play with your budget by getting some parts on sale that enables you to put more into something else. And if you have time to do it, you can see the prices for a couple weeks and get things as they fluctuate down. And some things you don't need right away like a better monitor or keyboard/ mouse, etc. Black Friday and Amazon Warehouse have DEEP deals. I buy "used" from the warehouse and save huge. There are no questions with returns for any reason. If something doesn't work, you put it back in the box and send it back. Has to be sold by Amazon, tho. Private sellers have their own rules, but Amazon Warehouse accepts returns for any reason.
The one thing you want to be careful of at any of the box stores is not getting boxed out of potential improvements you can make down the road. They aren't always clear on what's in the unit. The newest stuff is going to be at a premium, while some of the older parts are almost as good, way cheaper, and still have upgrade paths. If you buy the newest cpu, for example, both Intel and AMD have new sockets, so older CPU's are not compatible with newer motherboards those new cpu's are in. The older hardware will be backward compatible with the newer CPU's and Motherboards, but new cpu's won't fit older MOBO's and old cpu's won't fit MOBO's made with the newer socket.
I built a really nice one for my son last February. We started out building it together, which was fun, but it wasn't done in the first day, so he lost interest. It is crazy fast and plays everything from Fortnite to Red Dead to GTA. When I stop in to watch him, it's literally like watching a movie as he plays. Way more advanced than my old Nintendo Entertainment System. lol