It's called checking references. You don't hire a logger without doing some research. Around here, there has been so much competition that good, easy to work with loggers are fairly easy to find with a little bit of research.
Flagging cut trees isn't the best way. If loggers are so devious, they'll move the flagging. Paint works better, and paint the butt of the tree below the stump cut level. Maybe do a super secret mark of some kind. Walk the area after the loggers go home, or show up during operations. Talk with them. Maybe they'll point out a tree that needs to come out that you didn't figure on cutting. Or mention that they need more room for equipment. You can point out the tree that Uncle Roy planted and named and you don't want damaged or cut. In fact, walk the area with the logger BEFORE operations start.
If you feed the crew cookies and other goodies, they'll often try to do a really good job. Most of the crews around here take pride in their work, and have come to the realization that what they leave is what people will see and judge them by.
A contract is a way to back up what you want and what they agree to do. Oh, you might want to consult with a ....Forester. I believe that many counties back east have a county forester. Out here, our state DNR can help. Read up, and educate yourselves.
Look at the picture. What do you see? See that straight opening? Here's what it takes. The unit was already marked for what to cut. The logger flagged in those corridors (where the logs will be skidded) and then it was part of my job to go up and down each one and mark the additional trees to be cut so the skyline could be run through it. It is easiest to do that before falling starts. Then the fallers moved in and sometimes I'd get a phone call mentioning that I'd missed a tree, or they hung one up and out I'd go with my paint gun to approve and write it up. We all had to work together and these guys were great to work with and I've given them good references. They're stringing out what is called haywire in the photo. It gets hooked up to the bigger and heavier skyline and pulls the line into place.
Here they went ahead and flagged trees they needed to use for a lift tree. I painted them so they could drop the tree afterwards, legally if they needed to do so. We agreed to leave the tree on the ground because after the logging, another contract would be let out to drop a couple trees per acre to leave as wildlife logs.
Things can be complicated.
