Now. Don't wait. Firms almost always let “Great” get in the way of Good. They try to perfect their product before selling it. Revenue needs to come in at some time. Always sell the product before you've developed it. Make sure your value proposition is crisp and clear your B2B marketing needs time to generate the results you want. And you will need to build credibility for a start up by authoring solid meaty content with your point of view. Beta customer testimonials will be all important.
Have a SaaS go to market strategy. Give early adopters preferred pricing or lifetime access in exchange for funding. These early adopters have a strong influence on how the product is built so be careful not to go to client-specific. Make sure you build generically withing your defined niche. Try for 5-10 early adopters so you get broad representation. Focus on building the best minimum viable product (MVP) that you can. This approach guarantees you ONLY build a product and features that people will buy. Basically de-risks your entire business. During which you will learn a massive amount about what the market actually needs and will pay for. These early adopters will be your best sales & referral partners going forward.
Once the 5-10 early adopters are using the product and the system is nearing a go to market date, market like hell. The timing of this is critical. Depending on what you predict your SaaS sales cycle to be, typically beginning two sales cycles ahead of the go to market date. So if your sales cycle is 1 month long, begin marketing 2 months in advance. Go crazy at first. Generating demand, excitement, and anticipation, takes time and effort. Be sure to begin the marketing efforts well before the actual launch date (especially for the longer sales cycle for B2B Marketing). This will allow you to generate excitement for the product launch. In turn some of your first customers will be excited to dive into the new system and quickly become experts… which in turn become your greatest advocates.
It's important to be a revenue generating focused company. It pays the bills. The companies we work with started selling day 1. To end customers and investors. It allows them to find out real quick, if the idea is viable, and what features are needed right away, while generating orders. Cash comes when you have a beta that works. Early customers get GREAT terms, some maybe for life. All contingency orders. Investors, they are different, they know risk, and will decide on their own. You then can sit back and do some of the “marketing” stuff to fine tune growth strategies and talent acquisition plans.
For a similar take on this philosophy check out the B2B go to market strategy