Your numbers are probably correct assuming the statistic you have are 100% true (wich they just won't be unless you actually have tried to run the campaign)
Think of you adwords campaign as you think of SEO on a website. Meaning how is your landing page, does it equal to your product, is it fast to load, does it have any popups, is your domain name coherent to what your ad is about etc etc.
How is your ad written out, will it scare of the non-buyers and will it appeal to the buyers. Are your keywords in it (remember, the search phrase will go bold if you have thoose words in your ad). Will it be well written towards what you are selling and what people who tend to buy are searching for?
You can even do a radio training {{keyword}}
How will your CTR be, low, high. What is the history of your adwords account?
All of the above will affect your quality score and your quality score will affect the price you have to pay for your ad.
As I said before, go for a low daily budget, set a fair price on the bid (I would start with 0,5 on that one and follow it daily and adjust it to see where my qs lands) run it for two weeks and see what your numbers say.
DONT put a whole list of keywords in there, start with thoose two and develop it from there. Don't forget about localisation and skip third party site. Think quality score, quality score quality score (location, location, location)
Same disclaimer as last time
