If you want an hourly breakdown and your current service isn't providing one, you need to demand it, or simply find a new service.
Anyone billing hourly, one-man-shop or otherwise, ought to be able to provide an hourly breakdown.
(lawyers are used to billing in 6 minute increments, and while I think it's interesting to go over their bills, I'd pay them (at least my current firm) the amounts they ask too if they wouldn't provide me with a specified bill. I sometimes feel sorry for them, what kind of life is that, having to write down the time for every 2 minute email you write?)
If you don't trust your professional services suppliers enough to pay their bills without knowing what they did hour-by-hour, you need to find other people who work for you, because that's not a healthy relationship you have.