We're planning to sell a small ERP product that utilized PostgreSQL on the backend, targeting between 10 to 500 users per client. The management insisted on getting paid support for PostgreSQL, but the quote we got from various vendors around our region is not competitive or even prohibitive and more expensive that what we've been paying Microsoft for their support locally. We've been reliant on Microsoft products all these time. Only recently we started looking into alternatives.
I'm more supportive of using OSS and I've since pitched that we could develop the skill in house and support it on our own. Few months back, I've helped to transition a small team from TFS to Gitlab(PostgreSQL backend) and I've not faced any show stopping issues. I'm confident that PostgreSQL is matured and we don't really need paid support like we do with Microsoft/Oracle products.
But so far I don't have a strong argument. I would like to gather more information for my argument and also to understand what's norm when using OSS for enterprise application. Above how many users should one subscribe to paid support?