Jan, btw, can I make a suggestion? (and I'll post here for others to learn from as well).
It makes much more sense to lease the domain with an option to buy at the seller's inflated price. This usually helps get the leasing agreement, as the seller keeps the domain, but you get a test period in which to try out your theories, but don't have a steep upfront cost. Lots of guys do this.
You also build in first rights to buy at the agreed-upon price, so that if someone comes in during the lease period looking to buy, you get the first rights to buy it yourself.
There are a few companies that do this to brilliant effect.
