Good Metallurgical Microscope? 1

The metallurgists at my company bought an AmScope stereo microscope 10 or 12 years ago. Use is similar to what you describe.

They are pleased with it.

Unitron Versamet is my favorite. Easy to switch illumination modes, easy to run DIC and dark field.
Not very expensive.
Buy a good camera, speed and color depth are more important than raw resolution. And get good software for image analysis, try them and see what you are comfortable with.
You will likely want a good binocular scope for <50x macro work. Olympus makes the best, but they are pricey so look for a used one.

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P.E. Metallurgy, consulting work welcomed

Probably not necessary to remind you of this, but after seeing the complete installation that was necessary (and getting installed as we went), we decided against it because the microscope is only the last step.
We've had the same thought few years ago, and went through the same research. Visited the two labs we usually work with, and started acquiring materials as we went.

You'll need a band saw with a decent capacity (you'll always come home with a piece that doesn't fit inbetween the jaws), a press and base material to fit small pieces in a resin block (don't know the english word), a sanding/polishing table, lots of different grits, a selection of etchants (of which you'll use not enough, and end up throwing away lots of it because some expire fast after mixing), and finally the microscope. And because we work with some exotic materials, we'd also need HF, which is more or less potentially deadly, and NaOH, which without fume extractor cannot be used indoors. And outdoors is still not the best idea...

Dino-Lite makes a great USB alternative, which would probably offer you some versatility for DIY-work for around USD500. Works decent, after freehand grinding with a random orbit sanding machine with lots of different pads.
True micro/macrography should be sent out to a dedicated lab... my $ 0.02.