I heard you wanted mid-career freelance advice, so here comes some VERY EXCELLENT MID-CAREER FREELANCE ADVICE.
Do not spend any of your precious freelance minutes keeping track of what invoice number you're up to with each client.
Yes, I used to do this—because each client required a unique invoice, which meant a unique invoice number, which meant having a spreadsheet column where I noted that I was up to Invoice 15 with one client and Invoice 95 with another client.
WHY DID I DO THIS.
IT WAS SUCH A WASTE OF TIME.
I know you're probably thinking "what about the FreshBooks and the QuickBooks and the BookBooks and all of those invoicing softwares I hear about on the podcasts? Won't they, like, take care of that for me?"
Well... maybe. But a lot of clients want you to invoice through their proprietary system, or through a third-party system like Kalo or Bill Dot Com, which means you have to log in to their system to invoice instead of using whatever tool the podcast recommended, and those systems do not automatically generate a fresh, unique invoice number with each invoice.
Instead, you'll fill out your invoice and get the entire thing rejected because you already had an "Invoice 15" in the system, and then you have to do it all over again and that takes TIME, WHICH IS ALSO MONEY, I TELL YOU.
And then I was like "I'm just putting the current date on every invoice from now on."
So if I were to invoice a client today, it would be Invoice #073019.
If I were to invoice two different clients today, they'd both get Invoice #073019, because it doesn't matter if you send the same invoice number to two different clients. It only matters if you send the same invoice number to the same client twice, because then you will get an email from accounting if the invoicing software doesn't reject you outright.
This system is also helpful because you can tell, at a glance, how long an invoice has been unpaid. If it gets to be October and you still haven't received payment on Invoice #073019, well... time for accounting to get an email from you.
(Honestly, client-based invoicing softwares have pretty much eliminated late payments, so this isn't something I worry much about anymore. But it's still a good tip.)
So there's your MID-CAREER FREELANCE ADVICE for the day, as requested.
If you have additional requests for advice, let me know. ❤️