For the safe you listed, is there a particular reason you settled on it? All options security-wise or cosmetics? Is that particular size required or can you go with two smaller safes? $4k is a sizable chunk of money that opens up a lot of new avenues. It also depends on the contents. If it's something that cannot be replaced, you can go high security. If it's a collection that insurance will cover, it might not be as big a deal.
In general, a lot of the markup/cost on a gun safe is for the interior because people are willing to pay for a luxury interior. For example, Sturdy puts in a very functional interior and spends it's efforts on building a stronger box because they're more oriented towards security than cosmetics. It's why their safes are all batch sprayed in one color instead of doing a handful at a time in glossy hunter green, then another in burgundy, and perhaps four in piano black. As a result, your dollar buys a stronger safe versus other gun safes that'll give you lights, mirrors, and disco balls.
If you are handy, you can always do your own interior if you don't want to pay a premium for it and settle for a used commercial safe which can save you big dollars. Unless you're getting an exotic wood interior, it's just particle board with carpeting which is less than $100 in materials. Personally I never understood why people put such a huge premium on gun safe interiors. It's a box to keep your stuff secure. Unless you're always keeping the door open for yourself and friends or family to admire. Heck, maybe Fireking and Sentry needs to cash in and start offering luxury interiors for their fire safes
For example, AMSEC's top of the line TL-30 burglary-rated RF6528. Depending on cosmetic options, that puts you at $6-10k (prices vary a lot online and by options). Now look at AMSEC's commercial line, AMVAULT. The CF6528 is the safe AMSEC dolls up into the RF6528. They cost $4-5k. If I wanted, for $2-4k savings, I can have a cabinet maker build a nice interior, get a bodyshop to shoot a coat of paint, and still spend the extra buying another 3-4 guns...or just build an interior for $100 and live with the beige paint.
I've been researching commercial safes for several years waiting for the right time and product to pop up on the used market. There is a sizable price difference between used and new TL+ rated brand name safes unless the company is simply marking up the used safe by a lot. I'm not sure if you can haggle on prices but someone like Frank would know what they typically offer to buy old safes and how much they mark them up after reconditioning the mechanical bits. However I've noticed (what I assume are import) some brands offer new safes for a lot cheaper than the established brands so if they do come up used, they're even cheaper. Not sure how quality of the build stacks up but the locking mechanisms are still S&G typically. A website currently has a used 77"Hx43"Wx37"D TL30x6 safe for $4700. That'll defeat every single currently marketed gun safe (many of those well over $5000). The only downside is the excessive weight (which is beneficial for security). If you don't have a collection worth that much, then it's pointless to go this big. However if you're into the five-figure range on your collection, dealing with the weight by reinforcing floor joists or finding a concrete slab is a small price to pay.
A torch attack might not risk harming assets like jewelry, gold, or diamonds inside a safe, but a torch attack will risk harming firearms made of steel, wood, and plastic. It would seem that torch attack is unlikely even if the equipment was available because a burglar risks wrecking his loot. It's always possible your burglar is a tweaker with no brains but unless you have a torch in your home, I think the tweakers have already pawned any tools they own before resorting to burglary.
