Mining the surface is required; importing any significant quantity of material from Earth is a non-starter. Unless you can come up with something insanely valuable to export to Earth, any planetary colony has to be almost-entirely self-sufficient. Interplanetary transit is too long, and too expensive. (This is true on Mars as well, and probably Luna and asteroids as well, though you might find some edge cases there due to lesser gravity or greater proximity.)

The pressure on the surface is that of about 3000 feet of water, so that's not too bad, and the reducing atmosphere can be handled, but the temperature is tough. Still, with practice, you could probably build such machines. Dunno how you make electronics survive long term at ambient 465 °C (oil wells have a hard time with electronics at much lower temps) but some combination of active cooling, limited duration, and novel fabrication should be possible.

Perhaps the easiest solution is to load up your Venus Mining Hopper with a whole bunch of liquid nitrogen, extracted from the atmosphere and compressed and liquefied using solar power falling on your floating platform. It deflates its balloon and drops to the surface, and starts scooping up material into its hopper as the LN2 boils off, cooling the electronics and other temp-sensitive systems. (These are buried in lots of insulation.) When the hopper is close to full, you start venting the N2 into the balloon, and the whole system takes off again, to rendezvous with a solar-powered tug to pull it to your ore-processing factory. That may be a long haul, because the upper atmosphere of Venus moves at 100m/s. Maybe you design your system to stay on the ground long enough for the platform to come back around the planet, a mere 4-5 days. Or maybe it just takes a big bite and goes straight back up so it doesn't get too far behind.

So maybe doable, but it makes the hurdle for setting up a self-sustaining colony much higher. Not that it's a much lower hurdle anywhere else.