Best time to negotiate is before you're on the platform. Have seen numerous companies that managed to secure an increase cap for 2 renewals in their initial agreements, but have never seen someone get it later. They will eat away at your discount once you're on, because they know how painful it is to move. Used to be much more reasonable and less aggressive about it before Oracle acquired them in 2016. Had one rep tell me that post-Oracle acquisition I should expect a 5-15% YoY increase annually (and this was before all the inflation of the last few years). Best you can do is sign a multi-year agreement (and ask for a discount because of that) and try to minimize user/feature growth. Also start negotiating as early as possible, so they're not trying to pressure you into agreeing immediately. Nowadays, I think I'd be pretty happy with a 5% increase, and could probably live with even a few points above that, even if I would fight it/grumble about it pretty hard.