I bought some bath mats
When we moved into our current house, I bought some bath mats for our bathroom. The mats were super plush and felt great, but when you opened the door they would get caught and then the door would get stuck and then I'd have to yank the bath mat out.
My solution was to place the bath mats away from the door and then just move them in front of the tub/sink after I showered.
I did this for three years before I said "enough!"
I Googled "ultra thin bath mats," read some reviews from people who had the same problem, and ordered a set for around $50.
Now I live in bath mat heaven! I can just open the door smoothly and not have to tetris the bath mats around.
In 1099 life, there are going to be things you have to do that annoy you that could be solved for a few hundred bucks or less.
If you are regularly annoyed by a task or a problem that could be solved by money, just pay the money! Don't be cheap. Your mental health will improve like 1000x.
For example, if you're one of those people who think you can just get free open-source software instead of using Microsoft office and are always dealing with file compatibility issues, just pay for Microsoft Office dude!
Make some investments where the return is being less annoyed on a daily basis.
I'll caveat that sometimes the cure is worse than the disease. Here's a link to a WSJ article about people who need to print stuff but don't buy printers because almost all printers are crappy.
In my case, I just decided to spring for Adobe Acrobat Pro because most of my printing needs comes from needing to sign a document. When I do actually need to print I just print stuff at work.
Another nuance: don't pay for stuff before you understand what you truly need. In my book I advise you to do your invoicing/expense tracking/time keeping in a spreadsheet yourself. This is because when you start it will help you better understand your operations process. Buying software at the beginning is like buying a calculator before learning arithmetic.
However, once you get tired of maintaining an ugly spreadsheet, you can graduate to software that will do a better job than you can.
For my business I use a few pieces of software that integrates together, but if you stay solo, my wife really likes Freshbooks.
The cheapest plan is $17/month which seems worth it to not have to fiddle with invoice templates in Microsoft word or manually log your mileage.
If you have any purchases that made your life easier, please share. I'd love to hear about them.