I feel you on the multiple page thing. It increases abandonment like crazy. Here's our first hand experience:

We used to have a 5-stage ad campaign creation process in our SaaS self-service ad manager. Once we started measuring cart abandonment rates, we noticed that users dropped off after the first 2 steps. It gets even worse if you require users to sign-in first

The solution: 1. We replaced it with a 1-page process 2. This is the crucial bit. We allowed users to create their ads BEFORE signing up.

By seeing a live preview of their ads, we engage them early and dramatically improve conversion rates.

The morale of the story is that keep the steps short (even if the form is long) and provide instant gratification.

Here's a link to the form on our demo site : http://demo.trafficspaces.com/advertise/cart/new/?adspid=153...