All these items can be purchased from Funky Kong, for a price. Each item will help in some way, but they are not meant to be relied upon. It can become quite costly to do so, so it is more sensible and cost effective to use them only when you have no other choice.
Balloons
Blue Balloon
Blue Balloons are brand new to this game and will help out with those underwater levels. They will recover your character if he or she runs out of air, which is quite easy to do. Purchase a few of these for seven banana coins apiece before taking on the more challenging water levels.
Green Balloon
These handy balloons are incredibly useful for harder levels with multiple platforms, as they will save you from falling to your doom—most of the time. While they do not always work, they make those troublesome temple levels far more bearable. You can purchase a Green Balloon for only five banana coins!
Red Balloon
Purchasing a Red Balloon will give Donkey Kong an extra life. Doing so has the exact same effect as collecting a Red Balloon from within a level. You can buy them from Funky Kong for only three banana coins each.
Banana Juice
While Funky Kong may have no clue what this does, we sure do. This delicious concoction will temporarily make Donkey Kong invincible and impervious to any damage. Beware that this juice will not save you from plummeting off a steep cliff. Banana Juice costs 15 banana coins from Funky’s shop.
Barrels
Cranky Kong Barrel
Introducing the first ever Cranky Kong Barrel! Buy this for 15 banana coins from Funky Kong, and you will have a portable angry old fart from the very start of a level. Use this for levels that have a plethora of spiked floors, since his pogo stick cane will bounce across that terrain with ease.
Diddy Kong Barrel
Purchasing a Diddy Kong Barrel for 15 banana coins ensures that Donkey Kong will begin a level with his best buddy. This is one monkey you want to have on your back! Did we mention he has a jetpack??
Dixie Kong Barrel
The Dixie Kong Barrel costs 15 banana coins and will allow you to start any level with her help from the very start. She is by far the best for reaching items that are particularly high up, and is great for those fast-paced temple levels.
Capsule Toy Machine
The Capsule Toy Machine dispenses toy figurines of each character, enemy, or ally, in the game. While the Capsule Toy Machine may sport a cheap price tag of five banana coins each, the biggest issue is the high probability of purchasing duplicate character figurines. That being said, if you collect as many banana coins as possible, you should be able to collect them all if you dump enough coins in the machine.
Crash Guard
Using the Crash Guard in a level with a Rocket Barrel or Mine Cart gives you an extra damage shield, which might keep you from turning into a furry scrap heap. The Crash Guard costs 10 banana coins from Funky Kong.
Heart Boost
The Heart Boost adds an extra heart to DK’s heart count, bringing your maximum amount of hits from two to three. Purchasing this for 15 banana coins before a temple level or boss battle will significantly boost your survival rate.
Squawks
This feathery companion has an affinity for finding Puzzle Pieces, and he does so very energetically. Squawks will let out several shrieks while flapping its wings furiously if Donkey Kong is in the presence of a Puzzle Piece, so keep an eye on its movements throughout the level. Buy Squawks from Funky Kong for 10 banana coins.