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A lot of students asked about which account to use for their client projects and if they need to pay for the account plan.
So here are a few options when working with clients:
You can create a new free account for you client and build the website in there. You can either ask your client to create one and give your the login credentials, or you can do that for them using their email address. Just ask them to click that email confirmation link when they get it.
In case you are concerned about your client not paying you and running away with a website by resetting the account password, because it's their email address on the account, then you can use your extra email address (we all have a whole bunch of those).
Once you are done with the project and you got paid, then go to the Account Settings (not Project Settings) and change your email to your client's email address. That way you will hand over the ownership of the account to them.
The easiest and best option is to just pay for the Account Plan. That way you'll create all new client projects inside your main account and once you're paid you will be able to use a Project Transfer feature and transfer the site to your client's account. Or don't. You can keep them in your account since hosted sites don't go against your project limit of 10 under a Lite Plan and under a Pro Plan you get unlimited projects anyways.