You shouldn’t have to watch every pour yourself — that’s part of what construction administration and regular site visits are for. But if you want an added layer of oversight, hiring an independent inspector to check in at critical points is a legitimate and affordable option, often just a few hundred dollars a visit. The bigger protection happens before you ever hire: call references instead of just emailing them, and ask about the hard moments, not just whether the finished home turned out beautiful.
Every project has real difficulty in it somewhere — that’s not what you’re screening for. What you’re listening for is whether a past client felt like their builder was honest with them when something went wrong. A good reference call sounds less like “would you recommend them” and more like “tell me about a time something didn’t go as planned, and how they handled it.” You should never have to wonder whether what’s being built is actually what you approved and paid for — and the earlier you build in a way to check that, the less likely you are to find out the hard way.