I have a business plan that involves rolling out across several very large markets with only minor adaptations to the product (a SaaS). But even rolling out in a meaningful way in the first market will require capital that I don't have. Provided I can find an investor (it's own challenge), how do I structure a deal that gets some small capital but leaves me open to a better round of investment later (from this investor or another group) once I've proven that I can succeed in the first market?
Trying to raise money with no customers/revenue will always put you at a disadvantage when trying to bargain for any deal, and you will always end up giving more than you should.
What I would suggest is to carefully analyze which is the minimum runway capital that you need for the launch of the first market and to demonstrate that a need exists.
* Decide which is the market with the best chances to get customers on.
* Outline the bare minimum that you need to build and launch a MVP in that market (dev, PPC campaign ...).
* CLEARLY build a timeline of events and milestones linked to above.
* Add 25% to both money and time for some extra runway that you will surely need.
* Go and pitch to angels JUST for this initial / clearly defined stretch. If you have stomach for it, consider FFFs (Family, Friends and Fools) for launch (best possible deal).
* In any case, difficult to get something for anything short of 10%.
Another option, if you idea is really great, is to apply for an accelerator (there many, many) that will get you some cash, speed up your success/failure and give you some contacts for approx the same %).