Why use Pages? To generate invoice you usually need a template. With iSous you don't need to know HTML to design you own. Simply use a word processor and voila !. Insert merge field in your document (see Preferences for the list of merge fields). It is not necessary to use Pages to track you invoice and payment. If you want you can only record an invoice without generating a Pages document.
RequirementsMac OS X 10.4 or later, Apple's Pages (optional).
*Previously available here