Watch craigslist and other similar sites in your area. You can often find great deals on Weber gas grills there.
I finally got my Weber Summit 670 stainless (their top of the line model) for 33 cents on the dollar from a guy who was moving 5 states away and did not want to pay to ship it (it's very heavy). Had all the options, rotisserie and cover, etc... Yes, it was more money than you are talking about, but their more modestly priced gas models are often seen in your price range in my area in perfect condition. You can also find ones in need of repair and Weber has every part still in stock. It's not unheard of for someone to pick up a Weber needing some TLC for
$100 or less and put another $100 and time into restoring it and have what would be a $500 to $700 grill if bought new. And Weber's are built to last.
As much as I love charcoal and smoking, there is still something to be said for the connivance of a gasser. Quick and easy to use and they still have their place. The wife will not use any of my charcoal units, but she will use the gasser when I'm not home in a heartbeat. And there is a lot you can do, especially with a good quality gasser like the Weber units.
Here is my S670. It's built like a tank and weighs a ton (no comparison of the quality with the stainless grills you find at big box stores). The photo does not really do the size of this thing justice. it's over 6' wide. All for .30 cents on the dollar and proud of it.