What to do with an invention

[bexta]

Hi!
I recently came up with an idea for an invention that is not currently out in the market and it does not have a patent on it.
I have done my own little bit of research and I have also contacted a company who claim to do all of the work for you.
After speaking to them for many hours, they have said they will do all of the work, research and future stuff on the condition that I will give them the 1st oportunity to buy/produce the product.
I was just wondering if anyone else has ever had any experience in this area, if so what happened?
And also, if they come back to me and offer to buy it from me how do I know if it is a far offer or not?

[danchip]

who was the company

[bexta]

Its the Inventor Link, is that bad?

[danchip]

how is it going with the inventor link