My almost 30 years experience as Cartoonist, Illustrator and other graphic areas, are my work's warranty and my quality
From my school's years, I was work in graphic areas... making cartoons, people's caricatures, etc.. and then, years after, i taked my art in professional way, working in design companies.
This is simple. Client must contact me (e-mail) and tell me his/her proyect, I'll make the work, then, when i finish, i'll send a low resolution version of work... for aprove it. If my work is aproved, then payment must be made and i'll send the final high resolution version.
If is not completely aproved, first change in product will be free. The other changes will have a cost of 15% of the total price of the product