There's a slight learning curve but I've been very happy with GnuCash. It supports multiple accounts and containers, has decent reporting, invoicing, categorizing, etc. I also really like that it's offline. https://www.gnucash.org/
GnuCash is, let’s be honest, crap. Don’t get me wrong, I appreciate it, it’s totally free, but it’s crap.
However, it forces you to learn how to do proper double-entry bookkeeping. You’ll get it wrong a bunch of times before you get it right. You’ll Google stuff and be frustrated that you can’t find an answer. You’ll just learn, somehow. But then...
...one day something clicks. And that day, you realise why this system has been the way that accountants do things for literally half a millennium [0]. It’s extraordinary. It’s impossible to lose track of money. The benefits are far too many to explain here, but just trust me when I say that when you ‘get it’, it’s like a transcendental moment.
So how do I plan my future? I put in speculative transactions. I forward-plot my income based on work done, invoice payment dates, and known tax office obligations. I play with the future, what-if this, what-if that. This is all really manual, in this software that will undoubtedly frustrate you, but the control you have is unmatched by any smart online Web 2.0 software. It’s like being in the Matrix of your money.
So yeah. GnuCash. Shite, but amazing.
[0]: https://en.wikipedia.org/wiki/Double-entry_bookkeeping_syste...