Manfroto makes good tripods for moderate prices; for much work the tripod is for psychological effect, and for subject respect for the situation, and for better framing and for repeatable sequential images, where the camera or backdrop need to remain mostly "fixed" in one place, or one height, or one magnification.
Flash? For on-camera type speedlight flash, I recommend mid- to high-grade speedlights of the camera maker brand for 100% compatibility and reliability of a single unit, meaning Nikon camera? Nikon SB-700,SB-800,SB-910 flash units for d-slrs, not the little 400 model, Canon camera, 580 EX-II or 600 RT Canon branded flash, not 430EX! If you buy Yongnuo or Neewer flash units, make SURE you have at least one spare unit for every job you go on. Not kidding. Same with $20 MIC trigger sets! Cheap equipment like this is easily supported by its low price with one, or two, spare units.
Buy flash units that have automatic flash options. Again, this is why camera-maker flashes are nice; they WORK with your camera, and are almost guaranteed to work right, for years and years; the same is not true of $59 MIC flashes that are often less-powerful, and which might, or might not, work perfectly with your camera, in all modes.
For me the Nikon SB-800 speedlight has been good, but for "pro" studio-lighting type flash work, the Paul C. Buff company's Alien Bee 400 monolights (2 units), a set of triggers, a spare PC connector cord in 15-foot length, and two light stands and a pair of umbrella boxes ($645-$725 total, more or less) is a great basic kit to have for appearing "serious", and also for being able to actually light something big, adequately.
Buy multiples of the same model of flash unit, to keep familiarity high.
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