You don't need to pay anything. The express line of Visual Studio can be used to develop commercial software for free. For most circumstances developers don't pay a fee to Microsoft in order to distribute their software. If your software is dependent on certain MS technologies that are only available as part of a larger application then your customers would need to purchase that software.
Since you are just using an Access database as a data store then you don't need to pay anything to MS and your clients don't need to get MS Access. They just need to have this redistributable.
That being said MS is trying to discourage using Access as a data store of a distributed application. From the same page:
The Access Database Engine 2010 Redistributable is not intended:
As a general replacement for Jet (If you need a general replacement
for Jet you should use SQL Server Express Edition).
As a replacement for the Jet OLEDB Provider in server-side
As a general word processing, spreadsheet or database management
system-To be used as a way to create files. (You can use Microsoft
Office or Office automation to create the files that Microsoft Office
To be used within a service program or web application that relies
on a Windows service.