TELEPHOTO LENS (Medium Range)
There are many choices for medium telephoto lenses. A great range is 70-200mm and 80-300mm or anything similar. Lenses such as 18-200mm offer an incredible range of focal lengths, but the price you pay for this convenience is that they are not as ‘fast’ as lenses with a more modest range. By ‘fast’ I mean that the maximum lens aperture is not impressive. They will typically be f/5.6 or f/6.3 at the largest aperture.
This means when photographing in low light such as the Montezuma oropendola from Costa Rica that I shot under a thick cloud cover, the shutter speed won’t be as fast as it should be unless the ISO is raised.
On the other hand, slower lenses are much less expensive, and they are lighter as well. I used to own the Canon 70-200mm f/2.8 IS medium telephoto. I loved it for 10 years because it’s fast and sharp, but it’s heavy (I've since replaced this lens with the Canon 100 - 400mm). To lighten your load, the Canon 70-200mm f/4 IS is a great choice. It is quite a bit lighter and many hundreds of dollars less expensive, too. It is also a smaller lens. This is what my wife uses. She only weighs 98 pounds, so she really appreciates the ease of using this lens.
My other medium range lens that I use all the time is the 24 - 105mm lens. I use this to shoot people, festivals, architecture, and many other subjects. I didn't own this lens for many years, but once I got it, it became indespensible to me.