Viviana, Just curious how did you come to be in contact with this client?
The way he's asking for a 'bid' leads me to believe he's been using the freelance bidding sites quite a lot.

If I were faced with this situation, I'd write back to the client with as much information as I can about my skills at internet research - perhaps provide a case study of a similar project done and how the results were beneficial or profitable to the client and then I'd close with a statement on my hourly rate (or retainer, if that's what you offer.)

Asking for a per-project *bid* on something like this is the same as asking for $4 per hour....(in my estimation). Particularly considering the scope of the research.

Treat it like any other potential client (he/the project sounds reasonably legitimate to me) but be clear about your rates. Don't be disappointed if this client decides to go elsewhere based on price - if he is accustomed to using the freelance bididng sites then he has been getting work for $4 per or even less.

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