Spreadsheets are a fine start for invoicing. They stop being fine when mistakes and lost time cost more than a proper system.
Signs it is time
These problems tend to appear together.
- Two invoices share a number
- Nobody knows who has not paid
- VAT is added by hand and sometimes wrong
- Quotes and invoices live in different files
- Month end takes days
What a system adds
Numbers are never repeated, VAT is calculated the same way every time, reminders go out on schedule and one screen shows who owes what.
What to keep
Move your customer list and price list across, keep the old files as an archive, and agree the invoice design before you start so nothing changes for customers.