Project Overview
The project “A&K Project ERP Software Testing” aimed to systematically test comparatively evaluate ERP and accounting software for commercial processes in micro-enterprises (SOHO), self-employed professionals, and freelancers. The focus was not on the functional completeness of the tools, but on the quality of input validation,, die the stability of typical use cases and usability in day-to-day work.
Six solutions were examined: Sage 50 Connected, SevDesk, Papierkram, Zoho Books, Buchhaltungsbutler and MonKey Office 2022..
Initial Situation
ERP and accounting solutions form the basis for key commercial processes such as invoice creation, quotation management, master data maintenance, document management and payment processing.The demand is particularly high among SOHO users and micro-enterprises, while resources such as time, budget, and IT expertise are often limited.
In practice, this leads to typical challenges such as:
- incorrect entries caused by unclear or insufficiently validated input fields
- data inconsistencies (e.g. incorrect postal code, IBAN, or email formats, implausible values)
- higher error-related costs due to manual corrections and media discontinuities
- dependence on intuitive usability, as lengthy onboarding phases are rarely feasible
The project therefore addressed the question of how robust and user-friendly commercially available solutions actually are when handling standard business processes.
Approach & Methodology
The project was organized as a team effort, with each team member testing one software solution and documenting the results in a structured manner.
Methodologically, a black-box testing approach was used, meaning there was no access to the underlying code base. This was combined with tests based on equivalence classes.Standardized input values included:
- positive and negative integers
- strings
- combinations of strings and numbers
- special characters and mixed input formats
These test values were applied to input fields in key use cases and compared with the expected system behavior.
The approach included:
- research and selection of testable software solutions, including trial versions
- definition of a common test plan to ensure comparability
- execution and documentation of tests for each use case
- additional evaluation of non-functional requirements (e.g. UX and ease of use)
- final scoring (scale from 1 to 10) based on defined criteria, including:
- general functionality
- user Experience
- access and cost
- quality of input field validation
- customizability
Key Findings
The tests clearly showed that even established systems exhibit recurring weaknesses, particularly in input validation and plausibility checks.Typical issues included:
- free-text fields without format validation (e.g. email addresses, IBANs, postal codes)
- implausible values being accepted (e.g. negative dimensions, weights, stock levels, or percentages below 0 or above 100)
- inconsistent validation rules (e.g. minimum length checks instead of semantic validation)
- in some cases, heavy reliance on dropdown menus, which can improve consistency but may also reduce flexibility
At the same time, the analysis confirmed that:
- many tools offer a very good user experience and are quick to learn
- standard processes (invoicing, quotations, contacts, item management) are generally well supported
- the main differences lie in validation quality, customization options and value for money
Results & Comparison
The results were consolidated in a comparison matrix and presented as an overall evaluation. The following solutions received particularly strong ratings:
- MonKey Office 2022 – strong customization options and solid overall performance
- SevDesk – highly intuitive operation, strong UX, and good value for money
- Zoho Books – good usability and the possibility of integration into a broader software ecosystem
A recurring finding across almost all solutions:
The functionality of input fields (validation, plausibility checks, restrictions) performed weakest compared with UX and basic functionality and therefore represents the greatest potential for quality improvement.
Added Value & Knowledge Transfer
The project demonstrates how methods from business informatics, including testing methodology, comparative evaluation, and quality criteria, can be applied to real-world software selection and implementation decisions. The specific added value lies in:
- a comparable, methodologically structured evaluation of commercially available tools
- practical insights into where incorrect entries occur and how systems could guide users more effectively
- a decision-making basis for SOHO users and micro-enterprises when selecting a solution based on requirements such as usability, cost, functionality and adaptability .
The project therefore contributes to the quality assurance of digital commercial processes and supports small organizations in selecting suitable systems for their day-to-day operations.