Hi @JodieC
As @FaradayKeynes says - you’ve come to the right place 
We have a package that has been designed for accountants, bookkeepers and those with multiple accounts, called Affinity, which I believe would be suitable for your situation.
Affinity allows you to connect to individual QuickFile profiles (e.g. your clients) to provide the service you do for them. It also allows you to have just one email address and password and give you an overview of connected accounts.
Affinity works slightly different from the individual profiles, in that the fee is charged daily (paid monthly) and is based on the size of the individual profiles, which is graded from XS to XL. There’s a calculator here to help work this out. This can be paid by credit/debit card by top ups, or direct debit.
I’ve also included a few links below for you to have a look at, which outlines Affinity in more detail. But Affinity does come with £10 free credit, so you’re more than welcome to sign up and take a look around
Any questions, please do let us know.