Why do trades get to be paid instantly or it's trouble.
Because when you're self-employed, you get to set your own T&C's - be that payment in advance, payment upon completion, or payment within 48 hours, 14 days or three years.
I require payment within 24h of completion. If customers aren't happy with that, they're free to find another dog walker who is more relaxed about payment, but I have better things to do than spend my free time chasing up payment from people who just can't be arsed to pay me on time.
Luckily in nearly three years of business, I've only had one client who repeatedly paid late - so, as per my contract, I messaged her to say that all walks were suspended until her account was up to date. Funnily enough, she found the time to pay me then 😉she also never paid late again!
However, all my other customers respect me and what I do, and have the common decency to pay me on time.