ORIGINAL: Siefring
The Hobbico Superstar 40 RTF is $280 at Tower, but there is a $50 rebate. Add a Hobbico Field Pack with all the basics for $49, some fuel and couple of extra props and you're ready to go.
Is the $50 rebate right? I found a $10 rebate for the Superstar, $25 for the Avistar and $50 for the Nexstar.
Another formula for under $300:
Tower trainer $70
Engine $80 (OS, Thunder Tiger, Magnum, GMS, Tower, SuperTigre take your pick)
Futaba 4YF $130
Misc stuff $50 (spare props, glow plug, battery, glue, etc)
Total is $330. Now start working the discounts. First time order can get $20 off a $50 order. Use this for the engine, plane, or the stuff. Next order gets the $25 off anything over $175, which still keeps it in the $300 range. If the timing's right, additional discounts are often available. The bottom line is that with careful shopping, and avoiding the things that are nice to have, but not absolutely required, it's easy to stay in the $300 range. However adding in some of the nice to have things (and expensive club initiation fees and dues) can quickly push the total to the $400-500 range.