I just bought one for $45 at walmart also! it was the Backyard Classic 30 quart. I dont know how to make the burner stay on though. It didnt have any instructions with it. It has a timer and a button on top of the timer. Some kind of sensor or ignitor. I resorted to a piece of wood and string to keep the button pressed down so gas would flow.
It easily and quickly smelted the lead.
Everytime I would scope out some lead it would look like I needed to dross again...I didnt but I am pretty sure I should off\.
For ingot molds I bought a square muffin pan. works nicely. the ingots just drop out and stack well.