If you're looking to use a tool only a few times, just a money savings reminder that you can always rent gear instead of throwin' down some hard earned cash. I showed up on the set of the music video (above), and plenty of lenses, cameras, Redrock Micro rigs, and more were all rented from BorrowLenses.com. Specialty expensive lenses like the Canon 400mm F/2.8 that normally run for over $7,000 can be had for about $248 / week.
Sure sounds like money you could be putting towards owning gear, but talk to a few pros and you'll find out that a big part of the business is rentals. Most pros consider a project and throw the rental fees into the contract. I've rented a crazy 72" softbox and Profoto strobe/battery setup for a photo shoot for a mere $40 dollars a weekend, and that gear was well worth over $4k. I knew I would only use it once, and by adding it into client fees, it just makes sense. Find yourself a good solid rental place, and you'll really expand your work. You'll be able to take on larger projects and consider a whole new variety of ideas. One of the easiest most highly rated Rental place is BorrowLenses.com. Don't let the name fool you, they've expanded quite extensively and I believe are in their third move to a larger warehouse. You can rent DSLR's, Lighting, Audio, Camera bags, and even Computers. There's a long list of gear you should check out to help plan your next shoot. If you're new to the rental game, start with something small. Once you get the groove, you won't feel so limited taking on future projects.