Consider what you shoot:
Do your shoots move fast enough to require automatic zoom or or do you usually have time to move into a better position?
Zoom lenses have a focal length range such as 24-70, 70-200, etc. Prime lenses have a single focal length such as 35mm, 50mm, 85mm, and so on. You ‘zoom with your feet’ if you have a prime lens 😃 Prime lenses have better quality glass since there isn't a moving part in the middle, and are thus more on the expensive side.
Prime pros: better glass, you have to work harder, think more, and be creative for the shots you love,
Prime cons: more expensive, you have to move more often to get the shot, depending on your style you may need more than one lens
Zoom pros: one lens does the work of several, gets you close to action without being obvious
Zoom cons: lower quality glass, can lead to a bit of laziness if you aren't careful
Consider renting before you buy:
Once I rented the Canon 70-200 2.8 more than 3-4 times in a year, it seemed wise to purchase my own, as rental fees do add up eventually.You can rent very high end gear for a relatively small price to be sure you really want to invest in it. So that lens you’ve heard people raving about, or body that looks p.r.e.t.t.y. neat is now very accessible (yay!)
Places to rent from:
LensRentals: My favorite so far, especially if I can have a reason to rent more than 3 things in a year so I can take advantage of a whole year’s shipping at $79.
ApertureRent: My friend, Kathryn Grace really enjoys this service, and use this code to get 10% off your rental with KGRACEBLOG
BorrowLenses: the cheapest option if you need something ASAP, although I’ve found their packaging to be flimsy, and occasionally smoky-smelling.
Consider buying used & off-brand:
People go through phases and very often sell gear at great discounts. All of my gear (except flashes) is used. It pays to be patient and hunt for deals, and if you change your mind after using the gear for awhile, you can resell it!
Tamron & Sigma (among others) have made great strides in the lens world, and sometimes are better glass for a cheaper price than Canon or Nikon (hoping to save up for a Sigma 35mm 1.4 later this year myself). Facebook is rather invaluable when it comes to gear-talk. Join photography groups, search for lenses within the groups, and you’ll discover lots of image examples and reviews. Often people will ask a group “X or Y lens? Spam me with examples!” and ta-da! Lots of prettiness to look at!
Places to buy used gear:
Amazon (I purchased my 70-200 here, they also have better policies than eBay)
Two used gear groups on Facebook (I purchased my Canon 5D Mark I & II bodies, and 50mm 1.4 lens from here)
Keep record of your gear’s serial numbers in case they get lost or stolen.
Add your rental fees into your session charge so you’re covered.
Get the shutter count of a used body before you buy and check it against the lifespan of that model's shutter. Shutters are replaceable, you'll just be without your camera while that is done.
Get your lenses calibrated to your bodies so it's easier to get sharper photos.
The bottom line? TRY ALL THE LENSES. Okay, maybe that's a gear nerd's dream, but it's really up to you to decide what gear works for the vision you have, no one can make that final decision except for you. If you look at the process as an adventure, it's not so intimidating. And as you can only use one lens at a time, one lens is plenty to start with. YOU are the photographer, the gear is merely a tool to make your dreams a reality. I used the cheapest Canon 50mm lens (1.8) for years before adding the big zoom only last year. Even now my 50mm 1.4 lives on my camera body, and I forget I own my big zoom sometimes :D All that to say, enjoy the journey of collecting your tools, and if you need encouragement or more advice, don't hesitate to drop me a line. I'd love to hear how it's going (orrrr if all of this goes over your head).
Your photo comrade,