WordPress – Simple Customer Portal

I have a website intended for a single customer (multiple branches).

I want to be able to limit access to the website to customers set-up in the back-end only. So first they will be invited to login, then shown a welcome screen which shows their own (branch) information. Having created a Basket they can select Place Order, be asked for an order number and then the order will be submitted.

I have spent the morning researching the various plug-ins that would enable me to achieve my goal but most seem seem far too complicated for what I need.

Thnking that a members only and purchase order plug-in may be sufficient. But I have also read about people combining the “capability manager” plugin and “user access manager” which seems to work well with WooCommerce products?

Am I missing something?