I'm actually meeting with friends next week to show them how easy it is to apply and to convince them against hiring a consultant.
When I spoke with a consultant (who is not even a lawyer to begin with), we had a very bizarre exchange where she wanted me to use as much work experience in my profile as possible, including for the years that I have been self-employed. I was fortunate enough to have a lot of points to spare, so I saw no need for it.
I decided not to hire her and used only 1.2 years of experience in my primary (and only) NOC for which I could easily have a reference letter. For the rest of the years I marked myself as unemployed and explained why I did this in my LoE. I had only ever claimed 1 year of foreign experience to begin with going into the pool and that's what I stuck with through the ITA and AOR.
I would have to put together a pretty exhaustive list of documents, client contracts, invoices, testimonials, salary slips, yada yada, to prove my self-employment to IRCC. The consultant was convinced I should put in the effort, and that’s where we parted ways.
I did my own. Being in control and seeing the status directly the whole time was great. I don't know why anyone would need an attorney or consultant for Express Entry.