> you have to get a 90-ish day runway going so you don't feel like people are ripping you off when it's just the way the business world has worked for ages. 10

> you have to get a 90-ish day runway going so you don't feel like people are ripping you off when it's just the way the business world has worked for ages. 100% this. Every self-employed consultant must have plenty of cash reserves. It's not just to keep their personal finances solvent but also to maintain a positive relationship with the client. When consultants brood over invoices taking a few months, that angst spills into the personal relationships with the client and everything goes bad from there. If OP doesn't have a fully liquid cash buffer (I recommend 6 months worth), or if they don't like that invoices routinely take a few months to process, then consulting may the wrong career choice.