Service provider (gardening, handyman services) seeks billing software

I am looking for software for my service company (gardening, handyman services) that I can use to write quotes and invoices.

My requirements are as follows:

• Quotes, orders, invoices
• Mac OS compatible
• Email inbox
• All document archiving from and to customers, as well as invoice receipt
• Photographing receipts
• Archiving receipts and invoices
• Compliant with the principles of proper management and storage of books, records, and documents in electronic form, as well as data access
• Easy to use
• Optional DATEV interface (for tax advisor)
• I need an IT service provider who will come to my office, install everything, bring any additional hardware that may be missing, and set everything up with me
• Full IT consulting service, both now and in the future – the service provider should be based in the Rhine-Main area

For now, this is about one software workstation.