These days the cheapest place I can buy steel is $2.10/pound. There's going to be AT LEAST 300 pounds of steel in a really basic rotisserie. If you're not equipped to cut it places will charge a minimum 50 cents per cut, most are $1 per cut. You'll need a decent drill to do various sized holes and a decent welder to stick it together - not to mention the skill to use it. Add in some decent casters that will take the weight. And you'll be a solid day or more building it - anything less and I wouldn't put a car on it ! So yeah, you can build it, just make sure you understand what's involved.