On high priced sales, besides asking for the whole enchilada right up front, can you use a number of other, smaller offerings to build a relationship (gain trust, build top-of-mind awareness, etc). I call this selling on a gradient.
For instance, I have one client who offers high end consulting services. One client can pay the salaries of three people for a few months. But on their website, they also sell:
1) subscriptions to technical white papers (with some free samples)
2) an electronic glossary which stays up-to-date on the rapidly changing acronyms and buzz-words in their industry.
Sales of these items would never generate a stand-up business on their own, but as part of a whole picture, they keep people involved and principal clients have come from the ranks of the small buyers, over time.
You can't hit a home run with everyone on their first visit. So make it easier to score by also offering regular trips to first base. I'd say write with the long-term relationship in mind. Use all the sales power you can command, even when you pitch the freebies.