Double/triple your budget, or lower your expectations, or be patient and shop on the used market like Craigslist, and have cash and a truck/lift ready to go get it immediately...
It's like most other products - there is junk entry product, then there's the "sweet spot" product for about twice what the junk costs, and then there's extravagance. Consider a functional self defense handgun. $200 is typically junk. $400-600 is the "sweet spot." And $1000 is typically extravagance. Same with a formidable safe.
Thick steel is not cheap. Hardened locks are not cheap. Shipping is not cheap. Quality fire proofing is not cheap. Expect to spend $1500+ on a quality safe.
Thems the facts.
I also agree, buy larger than you think you need because you will quickly grow into it. It's nice to be able to put things like your laptop or electronics or other valuables in it when you go out of town for the night too.
Guns, coins, jewelry, ammo (which has become quite expensive), magazines (also quite expensive), electronics, documents, etc.
I have Sturdy Safes and am very happy. I've raved about them many times, you can find those links if you do some research on this topic, which comes up every week on forums.