That’s not what I would recommend for your needs. But your budget is also too small to do everything right, from the outset.
My first advice to you is to rent the right lights as each job comes along, and build the rental cost into the cost of the job, plus a little extra, to go into a bank account for your eventual purchases. $500 won’t buy beans for a lighting kit, but will rent an excellent one, a time or two.
Assuming though that you cannot rent, what I would advise in that respect is,
1. a pair of big softboxes. You would use these for lighting the green screen, and when not using them for green screen, they will be excellent key lights for interviews and stand-ups. One large softlight and a reflective bounce card on the opposite side for fill will make a nice setup for easy interviews. I always suggest the Lowel Rifalight as a softbank. Fast and easy to use and you can’t screw it up. An alternative is to use a spotlight with an attachment called a “speed ring” and some flexible rods and a baglike attachment called a Chimera, to create the same effect. Frankly, I think those are more bother than the Rifa, but if you already have a good spotlight, a Chimera attached to that gets you a softbank for less money than an entire separate fixture.
2. one or more open-faced halogen lights, or fresnel fixtures as a “hard” light that is focusable. When shooting green screen, these will be your key and fill sources while the soft boxes wash the green screen with a flat, even light.
You *could* use long fluorescent tubes to illuminate the green, but the softlights described above have more uses so I think you get more value for your dollar that way.
My kit that I use regularly is a Lowel make-your-own kit. It’s a suitcase that contains three Lowel omi pro lights, and one Lowel Tota-light., four light stands, barn door units, gel frames, reflective umbrellas that plug into any of these lights to turn them into a softlight. The RifaLight is carried in a separate bag.
That kit was expensive when bought new. But it has been in use every week for over twenty years, so when you divide $2k into that amount of time, it cost me 2 cents per day to own. You can get along great with rentals for a short time, but my rule about rentals is that if you rent it more than ten times a year, you should just buy whatever it is, as it will end up cheaper. A quality light also retains resale value so you’ll get a good portion of your money back if you decide to cash out some time. You can start your kit with used pro gear from reputable sources.
Yes, you can use your $500 to go buy some crappy Home Depot lights, and spend a lot of effort adding barn doors and flags to them, but they will still only be middling useable, and they will not impress paying clients. Don’t do that for more than a year.
Save up money, rent where you can, pass on the costs to the customer, and add a markup so you can build your owen kit up, a piece at a time.