Every CI/CD vendor uses a different pricing model designed to extract maximum cash while keeping you confused about actual costs. Here's how they fuck you:
User-Based Pricing sounds straightforward until you see the actual numbers. GitLab Ultimate runs like $100 per person monthly - so your 50-person team costs 60K annually just for licenses. Azure DevOps starts at $6/user which looks cheap until you realize you get one parallel job and your builds queue up like it's fucking 2005.
Credit-Based Bullshit is CircleCI's thing. They give you 30K credits monthly which sounds generous until a GPU build eats through them instantly. We had our ML team burn through the entire month's allocation in a few days because nobody warned them how expensive those builds are. Extra credits are like $15 per 25K and they fucking expire.
GitHub's Mixed Approach charges $21/user for Enterprise, then hits you with Actions minutes at $0.008 each. Our bill exploded to something crazy like 15K one month when someone triggered infinite recursive workflows. The billing alert showed up weeks later because of course it did.
The Hidden Bullshit That Will Bankrupt You
The reality: "Hidden" costs like compute overages, storage fees, and support charges will double your actual bill within months.
Your CI/CD costs will triple after the first year due to shit they don't mention in sales demos:
Self-hosted runners destroy AWS bills. GitHub wants 2-core machines with 7GB RAM minimum - that's like $150/month per runner on EC2. You need way more capacity during release cycles though. We went from 5 runners to 20 when Node 18.2.0 builds started timing out. AWS bill went from like $700 to over 3K monthly when you include all the storage and networking bullshit.
Premium support is mostly bullshit. CircleCI wants an extra 2K monthly for 24/7 support. GitLab includes it in Ultimate but you still wait hours for responses. Azure DevOps support is classic Microsoft - they'll tell you to restart everything and bill you for it.
Migration costs are insane. Moving from Jenkins to GitLab took us 8 months and cost probably 150K in consultant fees, plus all the internal time. Every plugin needed rewriting, every integration broke. We spent months just figuring out artifact migration. The consultant charged us like $500/hour to tell us to restart containers.
Docker registry storage sneaks up on you. GitLab gives you 10GB which sounds fine until your team pushes 2GB images daily. Registry costs went from zero to like $800/month in a few weeks. Nobody warns you about this shit.