"The best ********", and "budget" rarely go together. Make up your mind, and choose. Do you want budget, or best? You can reduce the cost of the best, somewhat, by buying used, or refurbished, and / or trading in something else. Even so, there are limits on how far you can go that way. For travel, you can get a reasonably good, but not great, superzoom lens...18-300mm, or such....or you can get a bag full of better Prime lenses. Superzooms offer lower total cost, and greater convenience, but sacrifice some image quality. The bag full of Primes offer better image quality, but cost more overall, and are less convenient to carry. If convenience, and budget, matter most, consider a Tamron 18-400mm lens. If image quality matters most, get a 20mm lens, and a 35mm lens, and a 50mm lens, and an 80mm lens, and a 105mm lens, and a 200mm lens, etc. Sometimes it will be best to get an in house brand that matches your camera...Nikon, Canon, or whatever. Sometimes, a third party lens-Tamron, Sigma, etc-will be better. Do research, and compare lens to lens, on cost, distortion, etc. $100.00 does not offer much in the way of possibility. Shop used / refurbished, and see what you can find.