InvoicePlane

InvoicePlane is a self-hosted open source application for managing your quotes, invoices, clients and payments. InvoicePlane is a solid application to manage your complete billing circle: from quotes over invoices to payments. The application provides CRM-like management for your clients. Enter contact details, notes or add custom fields. Basic project and task management is also available. You can customize InvoicePlane to make sure it fits your needs: select from different themes, set amount formats, modify email and PDF templates or many more. Let your clients pay the invoices by using one of 25 different online payment providers like PayPal, Stripe or even using Bitcoin via Coinbase.