What to buy?
I am wanting to buy a small studio setup. What is the best lens to have? Remote lighting? The camera I have is a Canon TSI with the kit lens 18-55. What additional lens would be good for studio shots. Just getting into studio photography. Budget would be around 700 to 1000. Any suggestions would be very helpful.
With a budget like that, I would put your money into lights. By the time you get 2 or 3 lights/stands/modifiers, most of your budget will be gone. If you are shooting with strobes, the speed of the 18-55 will be fine. Of course better glass would have better contrast, but you don't have the budget for that (unless maybe you went to the 18-55 IS).
If you had double the budget I'd say 24-105 + lights. The other option is a nice prime lens, but it doesn't sound like you have played enough yet to be able to pick the lens that will work the best for you and your shooting style.
There is no "best" lens, the one I like may be one that someone else can't stand, it is a personal decision based on how you shoot and what you want the finished images to look like. The 24-105 has good contrast and covers many of the focal lengths normally used in a studio (unless you have a huge studio) so it is a decent place to start. I would avoid the 17-85, 15-85 etc as they aren't that much better than your current glass.
Before you buy anything make a list of what you need and budget appropriately. At a minimum you need 1 flash (or strobe) a light stand and some reflectors (or foam core). The more lights you have, the easier it can be to get the look you want. A lightmeter is helpful and speeds things up, but isn't necessary. Background paper and stands is helpful if you don't have a clean backdrop. Light modifiers (umbrellas, soft boxes, snoots, grids etc) are incredibly handy, but get expensive quickly.
Good luck and have fun.