Guide or tips for selling a failed SaaS?

Hello!

I was running a SaaS for a few years, basically a tool for face-to-face sales (originally aimed at non-profits), with a hybrid app for the sales people to run on tablets and a control panel for administration staff to monitor sales performance etc. Reasonably comprehensive with a timesheet and bonus system, a geographic system for allocating territory and managing territory rotation, among other features.

I got a few deals going but wasn't able to make it stick more than a few years, so threw in the towel a couple of years ago and shut down the business. To be honest I was pretty drained after the experience, but always wondered if I could sell off the IP basically. Now I have the energy to explore the options!

There's a website, the code, marketing material, and a contact list for a niche market, as well as about 10 domains.

I don't know if people generally only buy businesses that have existing income or not? I was kind of surprised I couldn't find a group here about exits or selling, perhaps I missed it?

Anyway if any one has had a similar experience or could offer some tips it would be appreciated! Otherwise I guess I'll try flippa or one of those sites.

Thanks!