How to Join an Agency
What can be better than making money off your favorite activity? Photography business is great and one of the best choices for a creative person, there's no doubt in that. However, before you quit your current job you need to look realistically at it, and fairly evaluate your abilities and talent. The first thing that matters in terms of your reward is what you actually shoot or is planning to shoot. Below there's a basic list of most selling categories in order of what sells best:
6) Nature and wildlife
The first thing you need to do to get represented by an agency is to build a large body of unique stock photos. It's a mistake to think that stock agents are there only for established photographers; in fact, they are constantly looking for new talents. Both what you're able to do in the future and what you've done in the past are interesting for them. Another, and probably the most important, thing they want to know is how much will you be able to shoot and how good will the quality be. Remember that you won't have any significant chances to get in if you shoot what everyone else does. The thing is that the offer on the photography market is much higher than the demand, so if you shoot rocks, flowers and moss you probably won't have any advantages over people who shoot lifestyle or business pictures.
The first thing agencies do when you approach them is look through your work. They will spend their time and efforts for training you only if they see that you are rather talented and/or shoot something very unique. Some (not all) agents can give you a list of pictures for you to shoot. However, if you do get accepted by an agency, it means that they consider you a pro. Therefore they'll expect you to know how and what to shoot.
Nevertheless, some agents can offer some guidance and suggestions if you ask them. It is also important to remember that sometimes pictures take a very long time (maybe even more than a year) to find their buyer and make you money. So it's not a good idea to call your agent after a month after your pictures were submitted and ask about the money. It won't make your photos to sell faster, but can make your agent angry with you instead. Your main task is to shoot LOTS of images and submit them to your agency. Don't worry about the money that much at this point, have some patience.
Nowadays you probably will be required to be either exclusive or image exclusive with your agency. This means that you either won't be allowed to have any of your images at another agency or sell them yourself (exclusive status) or you will be able to send any images that you do NOT submit to YOUR agency to other ones or to sell them yourself as well (image exclusive status)
If possible, it is recommended to sign contracts only with agencies that grant you the "image exclusive" status. Otherwise, your stock income will depend completely from one company, which is not a very good thing. Signing a contract with an "exclusive" agency means you will do your entire stock business with one single agent and you will not be able to sell your own images yourself. And that is quite unpleasant situation indeed.
Being with as many agencies as possible may be a good choice to consider. However, you can have some problems with that since some agencies do well and some do not; each agency has its strengths and weaknesses. Nevertheless, if you work with several agencies at a time you have multiple revenue sources, thus, hopefully, more frequent payments and more money in total. Most agencies expect content from productive and highly committed photographers. The required amount of stand-alone high-quality stock images can vary from few hundreds (beginner) to several thousands (professional).
Professional photography is an extremely competitive business. This is the situation where survival of the fittest rules. Remember, it's all about volume. You can make $1500 per month with around 5000 photos online, or earn $20 with 200. So, as you can see, there are few possibilities for a weekend stock photographers. If you want to make money on it, you have to live in it.