I paid mine $1200 for the initial plan and $250/hr for any follow up questions, check-ups, etc.
His web-site advertised a higher rate, but I called and just offered a lower amount and he took it.

The plan was solid and I only needed to touch base for a sanity check year two. I've been implementing a few changes through the years per the original plan. I'm now in year 5 of retirement and feeling very comfortable. My NW is closer to $6m. At the time I found him I thought he was not charging enough (and ended up sending him a bunch of gift cards as a thank you in addition to his fee). I think he's a retiree himself and just looking for a hobby to fill his time.

I don't see the point in paying a large retainer. What do you get for that?