10 angel investments including Dollar Shave Club, Cabify and Geekatoo. Strategic adviser around fundraising (Seed/Series A), valuation, financial analysis and strategic planning.
I have ample experience valuing SaaS-based business models from my recent operational experience within a SaaS business and my previous experience in investment banking. Happy to provide more information, but a "good" projection model will require a strong (and well thought-out) operational build-up. The more details, the better.
You will need to provide more information in order to try and assess a reasonable value. The valuation metric and stage of your company will both be key drivers in trying to assess the value of your business. Earlier-stage SaaS models will typically be valued on a revenue multiple basis, but these valuations are more of an art than a science. Other factors include industry/sector-related KPIs, recent funding activity of similar companies and even geography. When you move into more mature SaaS models, EBITDA becomes a much bigger part of the equation. Happy to discuss further if you want to provide additional information.
While there is potential value in your industry databases and reports, that value is worth nothing if there isn't a customer on the other end. In order to viably approach external funding sources, you will likely need to bootstrap and iterate your business model until you show that your product has value in the marketplace.
I've been in the market before pitching a pre-revenue business and I can say with certainty that it is an incredibly difficult proposition. The companies that are typically able to raise capital in these situations feature founders with established entrepreneurial experience (ideally, with successful exits) or some sort of proprietary technology.
Best of luck, but my ultimate advice is to start small and build slowly. From the looks of it, you are putting the cart in front of the horse. I would imagine offering your product on a free or trial basis would allow you to promote in a cost-effective manner. At this stage, your goal is to prove the concept, so any progress here will also help with potential fundraising down the road.
Can't speak to the legal standing of the e-mail in regards to the initiation of a contract, but from my understanding it sounds like you would be in the clear. Dealing with a partner who "isn't carrying his weight" is always a difficult topic, particularly when you are talking about a 2-person partnership. Hard to make a clear judgment based on the information provided, but your partner should understand the risks involved with investing and co-founding a start-up. Unless the wording of your agreement was overtly biased towards your partner, I find it hard to believe your partner would be able to re-coup his initial investment.