Werkheft is back-office software for German solar and tree care businesses with 1 to 10 employees. It covers on-site measurement, quotes, work reports and invoicing in one app.
For solar businesses: a measurement app for PV roof surveys with photo and GPS, module and inverter templates, and the automatic zero VAT rate under Section 12 (3) UStG for residential systems up to 30 kWp.
For tree care businesses: inspection reports based on the FLL guideline, mobile photo documentation as evidence, and automatic Section 35a cost splitting for the private customer tax deduction.
Invoices meet Section 14 UStG, are archived to GoBD standards under Section 147 AO, and export in ZUGFeRD format for the e-invoicing obligation from 2027/2028. ZUGFeRD files are recognized by Datev, Lexware and sevDesk; a DATEV interface for tax advisors is included.
The platform works offline with automatic sync. Servers are in Germany, GDPR-compliant. From EUR 20 per month, cancellable monthly.
