I’ve done consulting work for 20 years including building custom manufacturing software. I’ll be honest, $100-150k for a custom MRP system is pretty low these days. Even when I was only charging like $75/hour many many years ago, they’re so complex that I ended up billing about $100-150k back then. If someone were to ask me what to budget for one today I’d tell them at least $300k. Considering average US devs are $100k-200k/year, that’s just two devs for a year at most. Not really that far out of line. What they did poorly was communicate what they were doing. It should never be a surprise when you get the bill. You should always know what the risks are in terms of going over estimate. And you should always have an escape hatch with a valuable deliverable, even if it isn’t fully finished. The only real way to do fixed bid software is if: 1. They are using an extremely battle tested and known framework (Rails, Django, etc) that they know very well 2. The software is of a type that they’ve done routinely for many years, with very few divergences, so they have comps 3. They pad it 50% anyway In manufacturing this would be considered insane but the reality is that most software development is more like R&D than it is like “build this part”.