Around here, in order to bring home over $700 a week, you need to make $50K+ a year, not $30K. That's claiming single and no dependents with the IRS, and no state income tax. To get that, in most cases, you need a solid and desireable skill set, a fair amount of experience, and an excellent work ethic.
People who make that kind of money in sales are the exception, not the rule, but it can be done. Your problem there is likely to be a lack of experience, and worse still, it appears you are in a fairly desperate situation. Desperation on a salesman stinks, and kills any chance at sales success, people smeel it a mile away.
The flip side is that I've seen people in urban areas that are doing decent economically make a fair amount of money delivering pizza in a cheap but reliable car (it's a Dave Ramsey thing, others mentioned him, he's a great resource). If you took a retail job for 1st shift (WalMart, box retailer, auto parts store, etc), or a warehouse type job (probably 3rd shift) and delivered pizza in the evening, you could probably make the money you want/need to make, at least for a while.