Interviewing small shop owners in Mexico

I need someone who is fluent in Spanish and English to walk around any major city of Mexico (Mexico City, Guadalajara, etc.) and interview several small shops to understand the way they manage their inventory. These small shops include apparel, house and kitchen items, jewelry, pet stores, beauty, food and grocery, health stores, etc. The interview will involve asking around 20 questions such as "how many items do you sell?" and "how do you discover new inventory?" and "where do you get your inventory from?". The interviewer will then need to translate the results from Spanish into English and send me the results. I will pay 10 USD / ~215 MXN for each completed interview with a bonus for high quality work.