MultiFlexx: bill processing ZZP-ers with self-billing in Transformer

Solid Online | Multiflexx

MultiFlexx has chosen Solid Online Transformer for the invoice processing of ZZP-ers. By using the self-billing (reverse billing) solution within Transformer , MultiFlexx and their ZZP-ers are assured of fast and error-free processing of all invoice data. This makes financial processing a lot easier.

How does self-billing work within Transformer for MultiFlexx?

Master data to AFAS

The master data of the ZZP'ers, suppliers and clients are imported into Transformer from FMS. A creditor is created in AFAS for the ZZP'ers and other suppliers. Already existing creditors are updated. Relevant data is imported, such as invoice type, invoice frequency and funding percentage. ZZP'ers can choose self-billing or receive a pro forma invoice containing all necessary information for invoicing to MultiFlexx. Other suppliers receive a pro forma invoice for commission or commission + wages (reinvoicing).

Placement and compensation 

On a weekly basis, the relevant placements, hours and fees are obtained from FMS and imported into the Transformer. The hours are automatically grouped in the Cockpit based on the billing data of the ZZP or supplier, taking into account the billing frequency, among other things.


It is possible to upload invoice attachments, which are sent along to the ZZP'er or supplier. In addition, a final check can be done on the content of the invoice or pro forma. This is then sent to the freelancer or supplier. A copy is sent to the administration of MultiFlexx, so they have an overview of all emails sent from Solid Online. After sending the self-billing, a financial transaction is automatically created in AFAS on the corresponding creditor. MulitFlexx's finance department can thus see at a glance when which amounts need to be paid. After sending the pro forma, a liability is automatically created in AFAS on the corresponding creditor.
Solid Online | Martine Verhave

Martine Verhave

Senior consultant Solid Online

"The down-to-earth attitude and honest disposition of Paul Verdiesen and Stephen van Houwelingen of MultiFlexx has ensured that within a few months we have put in place an Transformer application aimed at self-billing and reinvoicing that fully meets the wishes of the customer and also works optimally with the software packages that MultiFlexx uses in the recruitment process (Pivoton) and the financial administration (AFAS). The first introduction was on July 30, 2020, on location in Rotterdam. On January 1, 2021, MultiFlexx put the application into use. An achievement to be proud of, especially in these times when every consultation can only take place online. Gentlemen, thank you for your commitment, skill and thoroughness!"


Stephen van Houwelingen

Finance Director MultiFlexx

"Solid Online allows us to digitize invoices and proforma messages on behalf of the ZZP-er and hirer. This allows us to work more efficiently and pay the ZZP-ers faster. We especially want to thank Martine enormously for the fantastic cooperation on this project."

MultiFlexx was founded in 1994 and has years of experience and an exceptionally large network in the profit and non-profit sectors. MultiFlexx advises and guides the entire process of hiring temporary workers, seconded workers, freelancers, IB-47 workers, volunteers and trainees. They carry this out flawlessly, tailored to the demand of the organization. MultiFlexx is constantly working to optimize their processes, resulting in significant savings for organizations with many flex workers. MultiFlexx can also (pre)finance the full deployment of flexible labor. This gives the clients of MultiFlexx peace of mind in the workplace and no dissatisfaction with late payments. Flex workers can thus fully focus on their work and continue to enjoy working for the organization.

Is your company also ready for self-billing and smooth hour and invoice processing?
We would love to tell you what Solid Online can do for your business!

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