Ten real business documents, free to fill in and export — and a plain guide to which one you actually need, since half of these get mixed up constantly (a quotation is not an invoice, a challan is not a bill).
Roughly the order a transaction actually follows, start to finish.
A quotation is sent before work starts — it's a price offer the customer can accept or negotiate. An invoice is sent after goods are delivered or work is done — it's a formal bill requesting payment. A quotation is not a demand for money; an invoice is.