They've likely seen a LOT worse. Just remember the difference between a maid and a cleaner. A maid clears up the mess, a cleaner cleans the place. If your getting a cleaner, you'll need to make some effort to get the mess out of their way.

I've also found that's a useful effect. If you've someone coming in to clean every week or two, then you have a deadline and motivation to do your tidying. I don't want to pay a cleaner to waste time shuffling around my clutter.

The first time they come is really hard (so much shame), but it gets easier. I'm not going to pretend that I'm not sometimes up at 5am cleaning before the cleaner comes, though.

Just ask around and google. Word of mouth is your best bet for finding someone running a one person business, though you can look at any noticeboards in shops near you--my local coffee shop generally has someone with a flyer up. Yelp and Google will turn up worker-owned cooperatives, which makes me feel better about the ethics of paying someone to clean.