Don't base your decision on cost alone. Base your decision on profits and goals.
- If search position is important for growing your business or is directly responsible for generating or potentially generating significant revenues, I recommend and personally go with coded static pages. You might get away with WordPress in the short run if it's a completely new product or service and you're the only show in town for related keywords or key phrases. However, if it's a great product or service, it won't be long until the heavy hitters join the fray and then you'll need the best possible optimized site to hold your position.
- If site uptime is a critical issue, you may want to avoid WordPress. However, again, a lot depends upon who hosts your website, how it's protected from being hacked, and having a readily available backup.