If you're only painting Iron gating, I would just recommend Harbor Freight's Purple Gun with the 1.4 tip. It lays great for the price. Though I wouldn't ever use it to paint a car or bike, for a beginner it's a great entry door gun. If you want the next step up, I like the Kobalt HVLP from Lowes Home for around $100. You can also look into getting a mini gun, which has a smaller fan pattern for your project. Also, check out you local craigslist for "hvlp" and see if there's any good deals. Northern also sells guns by Vapor, for around $40-50, they look alright and have good reviews. They do carry a Vapor 3 gun setup too, if that's what you're after. Hope that points you in the right direction.