allow Google and other search engines to index password protected content - custom module

I want to allow Google and other search engines to index (but not cache) my content but I want to require registration for users to view all content. (I do not care about security issues or people using a user agent switcher.)

I am told this project will involve steps similar to these:

1) create an account to be used by the search engines

2) add in some php code in a custom module that:

a) checks $_SERVER[HTTP_USER_AGENT] to see if it's a search engine

b) if (a) is true, update the global $user with the account from (1)

3) add meta tag in page.tpl.php and other page-*.tpl.php in theme to not allow caching

There are two options I can think of:
1. simple version has static list of search engines in a config/settings file.
2. a smart version that can grab updated lists of bots and verify them against the IP address of the user claiming to be the bot.

I would be willing to make the custom module that is created by this project open source and freely available to anyone using Drupal.

Please give me a price (and tell me if you want to do the simple or the smart version) and give an estimated timeframe to complete the work. I will pay via PayPal after work is complete. I have hired people through this forum previously and I can supply references.