Hand presses or clamshell or elbow juicers are the most common type of juicer I see in the home and are also found in some cocktail bars which utilize al la minute juice service. friendly reminder that when juicing halves of fruit they go flat side down, not conforming to the bowl shape of the press. Cut Side Down! Older styles had a flat base to match and no holes for drainage of juice, simply a pour spout on the side to dispense the fresh juice. Newer styles have a curved bowl to cause the half-cut citrus to partially flip inside out along with holes at the bottom to allow it to dispense into a tin or other receptacle. An issue with these style of juicer is the variable size of citrus and you'll most likely need a different one for lemons, small limes, and larger oranges and grapefruit. Material is important when purchasing. plastics can break easily some metals are much more difficult to clean than others, especially when scuffed after extended usage. Amco is a good durable metal brand. Norpro is a bit more expensive but many experts swear by it. Chef'n Force does a good job and alleviates strain on the wrist but does have a shorter lifespan I've found.
Standing levered presses are very popular in homes and in bars with a fresh juice program in medium but not excessive volumes. There are two main types, those with gears and teeth and those with a hinged concept that acts more like a scaled-up hand press. Hamilton Beach is the most common brand of the former and has become quite affordable. At volume, these do tend to break down after a few months, but they work amazingly well for home use. The parts can't practically be replaced and tuned other than some simple cleaning and oiling. Ra Chand is a fine example of the latter. It also has a much longer shelf life and requires less care, cleaning, and maintenance. It is a little clunky to operate, especially on a high bartop.
Motorized Reamers are widely utilized by bars juicing high volumes of juices. these are certainly more expensive but they do last substantially longer, making up for the cost in the long run. The preferred brand is Sunkist. These are HEAVY and noisy. They belong in the prep area of a bar/restaurant not anywhere near the front of the house. the fact that you're juicing your citrus by hand leans to a lot of strain on the hands and arms. There's minimal contact with the skin compared to press juicers so not a lot of oil is extracted, but you do yield a substantial amount of juice. Also, your hands do get messy. Wear gloves. Even then your hands will slip on the oil of the skin and the fruit will spin like it was the pottery wheel in ghost.
Fully automated juicers like Zumex were my best friend at several of the bars I've worked at. All you need to do is fill the hopper at the top with oranges (you can do other fruits but it'll wear on the blades and other parts) and the machine will slice it, press it (with pressure on the skin to extract oil), and partially filter large pulp from the juice. It's load and forget, no effort or strain on the body whatsoever. They are quite expensive though, upwards of two thousand dollars. not economical for home bartenders but ideal for bars with a busy morning/lunch crowd that enjoys fresh juice.
Juice extractors are the best way to extract liquid fruit fruits and some vegetables. They are broken into two types: Centrifugal Juicers, and Masticating Juicers. Centrifugal juicers spin a blade around slicing and dicing. They're basically motorized food mills that you'd use in the kitchen. They shred the produce and spin it allowing the juice to drain through and the pulp gets separated into a bin. Masticating juicers work almost exactly like a meat grinder, forcing the produce between gears to extract the trapped liquid. Centrifugal juicers do produce a lot more food waste and commonly yield 20% less juice than their masticating counterparts. A con of the masticating juicer is that it doesn't handle large chunks very well without clogging and jamming. you can shove a whole apple in a centrifugal juicer with no issue. So Masticating juicers need some extra prep. Both of these styles are great for pineapples, carrots, celery, rhubarb, ginger, and any other dense or stalky produce. Centrifugal juicers do lead to a lot of air going into the juice which for the most part will dissipate in time, but some bartenders will juice oranges in these a la minute to create a really fluffy textural drink like a garibaldi. Masticating juicers also have loads of attachments which make them very versatile. All kinds of things, like almond milk, butter, iced cream, baby food, and even make pasta can be made with the right attachment. Masticating juicers also are usually about twice the cost of centrifugal juicers, both in the couple hundred dollars range. Preferred brands are Breville and Omega. P.s. never put a banana in these.