You just had a physical home inspection conducted on the house you are purchasing and . . . guess what? Not everything is "up to code." What does that mean? Is it a substandard structure? Is it an unsafe house? That it's a rotten deal? Well, that depends on a lot of things.
I am in my 15th year of performing physical home inspections and I am a licensed general contractor and home builder. I can tell you right now that a home I just built and sold in the last year doesn't meet current code. Is it unsafe? No. Is it a rotten deal? I don't think so.
If you built or bought the home several years ago and it complied with code at that time, why should you, the seller, have to be responsible to alter the existing structure, just because the rules have changed?
There are so many things involved in home construction that change regularly and items that are certainly real improvements. The advent of pressure regulators, electronic ignitions, dual-glazed windows, hard-wired smoke detectors, ground fault interrupters, stair and railing requirements, offer us improved consumer's health and safety as well as comfort and economizing.
If, as a buyer, you think it's a good idea to improve on some or all of these things, then by all means go for it. But don't expect the seller to pay for them. I regard these up-to-code improvements as "upgrades" and not repairs. Up-grades should be paid for by the buyer.
Big Bear City