Question of the day: How involved was your agent in the process of self-publishing? Do you/are you still working with her?
A good and relevant question, and one that I'm getting asked a lot.
To answer, my agent is still very involved in the process. Initially, a lot of the fact-finding, discovery and research was up to me. Neither she nor I had been down this road before, and while she supported my research, really, a lot of the work had to come from my end, since I was the one dealing with the nitty-gritty of hiring people, choosing a printer/distributor, copy-editing, etc. But she was supportive the entire time and certainly checked in and asked what she could to to help. She read the manuscript several times and weighed in on cover art and generally served as an advisor/friend.
Once the manuscript was finished, and the book entered the pre-publication phase, her involvement became more standard to what would happen with traditionals. She pitched all the subsidiary rights and sold many of those she's pitched; she chimed in on the film deal negotiations (I had a different agent for film); she is advocating the sale of the book to quite a few major retailers, which isn't something I can really do on my own as an author. From the business side, she's been invaluable (as always). But also, from the personal side, she's always been in my corner, which has been equally invaluable. Sometimes, when you take a leap like this, you just need to know that someone has your back. She had mine.
Do you need an agent to go indie? No. These days, you can record your own audio book, for example, and while I doubt you could sell subsidiary rights like large print and foreign on your own, these things may not be important to you. They were to me - and my relationship with my agent is also important to me! - so we both wanted to move through the process together. If you don't have an agent or don't want an agent, I'd just be sure to find a group of trusted readers or writers or whomever, who can offer opinions on things like cover art and jacket copy. A lot of times, you don't necessarily see the way that things can be improved until someone else points them out.
But can it be done alone? Sure. I'm glad I didn't have to though. :)