What you have described is a viable solution, however you should consider using the open toolchain for the iphone.
You don't need a mac then, only need to jailbreak the phone to make sure your app will work.
For all those who say it can't be done, this was the only way to make Apps for the iphone before the SDK was out :)
Also if you are after a guide to using the open toolchain then I highly recomend this book
