Some of the features you’re looking for led me to switch to Quicken a few years ago. It’s a legacy desktop app (Quicken Online sucks) and it’s not very fast but it is still the gold standard for personal accounting software. I’ve honestly been happier with it than I was with anything else I’ve tried.
Thankfully Intuit sold it off so they can’t enshitify it anymore.
About 12 years ago, I promised an agent at Safeco (AKA Liberty Mutual) that they would never get another penny from me because they wouldn’t honor the terms of my policy, refusing to pay the full amount on a vehicle collision claim. They’re just another business that doesn’t keep their word. But I absolutely plan to keep mine.
I would advise against it. Separation of concerns isn’t important until it is. If your host server is unavailable for any reason, now EVERYTHING is unavailable. Having your server go down is bad. Being unable to browse the internet when your host is down and you’re trying to figure out why is worse.
There are also risks involved in running your firewall on the same host as all your other VM’s without adding a lot of complex network configurations.
Since you’re already working in C#, an ASP.Net Core backed, with whatever database you prefer, will do what you want.
You could self host it, but I wouldn’t call that easy. There are plenty of cloud providers that can integrate with your preferred git repo and really streamline the build and deployment process. I run a few applications as “Apps” on Digital Ocean. Once you get it configured properly, deployments are quick and easy.