Founder salaries vary wildly depending on amount raised, whether the company is profitable or even generating revenue and the stage of the company. Some people pay themselves $1k/month and some pay themselves $15k/month. I figured $4k/month was a good benchmark based on a pre-series-A seed-financed tech startup that is generating minimal revenue and is not profitable.
While mocking up salaries with an adviser, he said that we should earmark $60k for founders "so people think you're stable."