How much should I charge for multilingual services??

Hi guys, Im a multilingual marketer (spanish and english) and I had not realized that selling multilingual sites in certain areas of the US could be a good business and an excellent way to make more money.

* Certain areas like Texas/Arizona/California/Florida are densely populated with both english speakers and spanish speakers.

Back to the business:
+ I believe that one should charge around $1000 USD for a simple 8-10 page corporate sites. (Law-accountant sites / health professional sites, etc)
- My service includes layout design, photography and proposal of ideal sections for their niche; my client provides the content for each section and I do the final edit.
- How much money should I charge per corporate web site if my client decides that he requires a bilingual site? This means I would have to translate the content. *Full website translation to native-like spanish

This is the website of an accounting firm in Miami, they understand the demography of their market and offer their website in both languages. If you click "Español" in their menu, you will get a translated version of their site; however they offer way less sections in the spanish version and I can sense that whoever translated the sections wasnt a native speaker.