I have used Clive before and agree with that recommendation. Also the others mentioned get regular good reviews here and on other trip advisor sites.
But making arrangements on your own is expensive. I saw a post that Rocky's Tours made on Floyd's FB page that I thought was a great idea. He started a regular Thu trip (said was a slow day for the sites) with idea of taking multiple people from multiple hotels to make it more affordable. Essentially a regularly scheduled group trip, rather than a private tour - with the price divided up accordingly. He goes to YS Falls, Black River, and Floyd's that day - not sure what order.
I can't say from personal experience because I have not used him myself - but have seen other posts that he is a good operator. Just an idea.
https://www.facebook.com/groups/10150090355875316/
