Accounting Start, Accounting Standard and Accounting Plus are priced at £12/£24/£30 respectively + VAT/mo (tier depending).
You can add as many users as you want to Sage Accounting. Use roles to choose what options each user can access, from read-only to full access. Our help section explains more: https://help.accounting.sage.com/en-gb/accounting/manage-your-subscription/user-management.html
Sage Accounting is an affordable type of accounting software that works from anywhere online. It's ideal for small businesses. Sage 50cloud is a more expensive type of desktop accounting software for advanced businesses.