Let’s talk
Stefan Diederich stefan.diederich@terqon.de +49 151 23937645 Detmold LinkedIn

SAP FI/CO · Order-to-Cash · Purchase-to-Pay · E-Invoicing · Controlling

SAP FI/CO from the first document to the financial close.

Accounting starts with billing and purchasing. That is why I design finance processes from their origin and fix errors where they arise, not in the general ledger. In Germany, companies with more than EUR 800,000 in prior-year revenue must send e-invoices from 2027, and all companies from 2028. Many are moving to S/4HANA at the same time.

A consultant who works hands-on in the system and takes on the project or workstream lead when it is needed. Both in one person, with no handover between roles.

25legal entities migrated in one S/4HANA brownfield conversion
10international rollouts implemented personally
15+years of SAP FI/CO, since 2010
9countries connected for e-invoicing

What I take on

Financial Accounting

Every error that arises earlier in the process shows up in accounting. That is where the system has to be right.

Over 15 years of SAP FI/CO, 19 country subsidiaries supported, responsible for a conversion of 25 legal entities as FI/CO workstream lead.

  • General ledger, accounts receivable, accounts payable, assets and bank
  • Credit management with SAP FSCM
  • Payments based on ISO 20022
  • S/4HANA conversion, data migration, cutover and release upgrades
  • International rollouts on a global template

Controlling

What has grown in ECC over the years can rarely be carried over one to one. It has to be rethought, not just converted.

Implemented CO-PA and expanded it over the years into group-wide contribution margin accounting, as a custom ABAP development.

  • Cost center accounting and overhead controlling
  • Product cost controlling and costing logic
  • Profitability analysis and contribution margin accounting
  • Assessments, allocations and derivation logic
  • Profit center accounting and Material Ledger

Order-to-Cash and Purchase-to-Pay

Complementing the core: once a document moves money, it is my responsibility.

Almost ten years of billing and pricing conditions in Customizing, incoming invoice processing rolled out to around ten companies, e-invoicing in nine countries.

  • SD billing, pricing conditions and pricing procedures
  • Rebate settlement and condition contracts
  • Incoming invoices and invoice verification (MIRO)
  • Inbound and outbound e-invoicing
  • Master data and interfaces to peripheral systems

Six months before go-live

A test run showed that the existing credit management would not survive the conversion. Order processing for 25 legal entities would have been affected.

This is not an isolated case. In migrations, the risk rarely lies in the module itself, but in processes that have run smoothly for years and are therefore rarely part of the test scope.

We rebuilt credit management from scratch, in parallel with the ongoing migration, safeguarded by five test iterations. The go-live weekend took 24 hours, and operations were stable from then on.

Why a single consultant

Direct access

You talk to the person who does the work. No account manager layer in between.

One point of contact

The same person from analysis to implementation. No handover between teams.

Delivery and lead

Customizing in the system and project or workstream lead in one person. No second person just for coordination.

Senior at every level

No junior team behind a senior sales pitch.

How we work together

  1. Initial call

    No obligation. We go through your situation together.

  2. Proposal

    Clearly defined scope on a time-and-material basis, no hidden costs.

  3. Start

    Remote or on site by arrangement, also part-time alongside other engagements.

Let’s talk about your project.

Location
Detmold, Germany. Remote or on site by arrangement.

Do you need support in day-to-day FI/CO operations, or are you facing e-invoicing, a controlling redesign or a move to S/4HANA? Write to me, and I will take the time for an initial conversation.

Get in touch
Call Send email