I'm struggling with this myself as I'm looking at lighting as the next frontier for equipment purchases. However, I've had great luck on the low end using Philips LED bulbs with certain inexpensive bulb fixtures, 5000K balanced LED work lights that seem to constantly disappear from the market shortly afterwards, and some of the newer inexpensive LED solutions like those foldable LED mats that are popular right now and just good deals on older used LED panels like Litepanel 1x1 lights. Newer and more powerful lights like the Aperture 300D II seem like great investments and cuts down on depending on my bigger 10-bulb fixtures and other exotic solutions but they're not only expensive but quite a handful for storage. I had at one time thought to purchase a couple of my own high end generators for filmmaking purposes but after filming my first feature last summer, I learned right away that I don't want to have to store and handle maintenance for generators and, yes, there is the gasoline smell issue as well. We rented from Home Depot as that was the closest available place to get them and that process was pretty seamless and convenient overall, so it shows that if there's someplace you can rent, in my experience, then that would be the most preferable situation. If you're in an area that doesn't have any rental places, well, then that depends on your budget and what your needs are.
As for cameras and lenses, I would say you should definitely have something on hand, even if it's an inexpensive set of still lenses (cine-modded or not) or a set of Rokinon Cine DS lenses. You never know if you might want to capture something or put together a quick short or even a test. If it's a good enough camera to bring you jobs, all the better, but I wouldn't go broke over a personal camera.