I think you have to know what your goal is first. If you're just trying to identify what sets may be present, that's one thing. If your going to sell it off in mixed bulk lots, that's another thing, and if you're planning on building your own parts library or bricklink store, then you have to go all the way.
I just went through a 90lb lot with over 200 figs that were all jumbled up - individual hands, legs, arms everywhere. Old Harley Quinn's head with Han solo's torso and one orange arm, one blue arm - that kind of thing.
First sort (1 big bin for each category): all bricks (including modified), slopes, plates 4x4 and up, plates that aren't a square or a rectangle, plates 1-wide and 2-wide (same bin), anything that's 1x1, anything with printing or a sticker applied, all wedges and hulls, all minifigs parts and accessories, anything technic (except bricks), and anything "interesting" (like a slope in a rare color, an odd vehicle plate, anything that might lead you directly to only a handful of sets). I throw things like telescopes, goblets, coffee cups, "flames", bones, barbs, binoculars, and loud hailers in with the 1x1's. And then 1 bin for everything else.
Second sort: the "everything else" bin gets sorted into big pieces and not big pieces. Plates get sorted into 1-wide, 2-wide, 4-wide, and 6-wide. Bricks get sorted into 1x2, 1x3, 1x4, 1x6+, 2x2, 2x3, 2x4, 2x6+, and everything else (1x1x5, 1x2x2, 4x8, etc.). Slopes (both regular and inverted in the same bin) become 1x2, 1x3, 1x4, 1x6, 2x2, 2x3, 2x4, anything thats 2 bricks tall, and everything else.
Third sort: 1x2 plates get separated into modified and regular. If you are trying to re-create sets, you'll spend a lot of time going through modified 1x2 plates, so you can certainly subdivide these. Same with 1x2 bricks. If you're going for sets or inventory, then technic gets sorted into axles, connectors, lift arms, pins, gears, and everything else. The "everything else small" bin from the 2nd sort gets all the handles, panels, seats, stop bars and light saber wands, and barrels/ trash bins/ container boxes pulled out. The "everything else big" bin gets all windows/ doors, and windscreens pulled out.
Target has these cheap bins that they sell in bundles of 5. I think they're 6qt bins with your choice of green or grey snap on lids. They're like $5.25 for 5 bins. I got 40 of them at first, and also used large Lego PAB cups for some parts.
That ought to give you a really good start.