There are many systems out there and it can be very tricky to find the right one, I always suggest to ask for a trial before signing up and commiting to any type of software. If that is not possible then read reviews carefully. Here is a link to my favourite place to read reviews and see pricing about software G2 website.
Quickbooks, Xero and Sage are best for growing or complex businesses:
- Link here to Quickbooks website
- Link here to Xero website
- Link here to Sage website
Freshbooks, Freeagent write up says that they are great for freelancers and sole traders:
- Link here to Freeagent website
- Link here to Freshbooks website