How much money should I spend on a safe?

As a cryptocurrency investor, I'm always concerned about the security of my digital assets. Given the rising threat of cybercrime and hacking attempts, I'm considering investing in a high-security safe to store my hardware wallets and other sensitive documents. However, I'm not sure how much money I should allocate for this purchase. Could you please advise me on the ideal budget range for a reliable and robust safe that can withstand potential break-in attempts? Keep in mind that I'm looking for a long-term solution that provides both physical and technical security features.