The last year saw a huge increase in the people starting a home gym. As someone that owns a gym and also has a decent amount of home equipment, I thought I would go from a slightly different angle if I had to start from scratch.
First, I'm writing for someone that wants to get strong, but not compete in the sport of powerlifting, olympic lifting or bodybuilding. 2nd, I'm writing for someone that doesn't have an unlimited budget, so choices will be made. 3rd, space is considered. These are the 3 criterium. If one of the three doesn't meet the filters you have for yourself then the list becomes less important.
Right off the bat, lets get the elephant out of the room. I am not going to list a barbell or a squat rack/power rack. Here are my reasons. I'm not enamored with barbell back squatting/front squatting or barbell deadlifting anymore. I don't practice olympic lifting. If you want to do these things, that is great, but just realize you don't need them to get strong and stay healthy. In fact, if you want to stay healthy, I'd advise, the average person against them anyways. If you want to invest in a high quality barbell that is an investment. A good one will run a minimum of 300 dollars. I'd go so far as to point you at Chris Duffins Kabuki Transformer bar at around 700 dollars for staying healthy and getting strong and its versatility. If money was not a concern, I would consider it at the top of my list. But if you get a barbell, you must get a squat/power rack. Again, minimum 300 dollars. (for the cheapest I can find). Also, a squat rack takes up space. Even the ones that fold flat into the wall. It's still there. A barbell often means you will most likely get a bench. Even a bench from ACME will run you a 100 dollars. Olympic lifting requires bumper plates. Very expensive when comparing to metal. But this isn't a list of why nots...lets get into what I would get.
Trap Bar with High Handles. With no moving parts, a trap bar is essentially a solid piece of metal. Nothing fancy. It combines the best of both worlds a squat and a deadlift. Depending on the set up and shin angles, I can make the trap bar more "squatty" or more of a "deadlift." With the center of mass at your sides instead of in front, technique is so much easier to learn. This translates into less back injury risk. I can teach someone good form in the trap bar in around 5 min. You are constantly working on your technique for a convential/sumo deadlift and front/back squats. Remember powerlifting is a sport. Research has shown you can develop more power using a trap bar then a conventional barbell.
The trap bar can also be used for Romanian deadlifts. Bent over rows. If you have room, farmers carries. The handles make a nice handle for elevated push ups. Jumping squats. I've even put the end of the trap bar in a corner and did a slightly modified landmine press.
Best of all it's like 130 dollars.
Metal weight plates. Actual weights are at a premium right now, but they can still be had. While I love lifting with bumper plates, less jarring. You can't beat the price of metal. 4x45, 2x25, 2x10 2x5 are what we are trying to get to. Since most trap bars are 55 pounds. This weight all loaded up would be 315. Even if you have a 500lb deadlift. 315 pounds for reps will keep you significantly strong. Remember, you can always add more weight as you go and or get stronger.
Cost is significant right now at around 2 dollars a pound. Precovid 50 scents a pound would be a standard for a craigslist of play it again sports. These are the times.
Heavy Bands. Bands are some of the most versatile pieces of home equipment you can purchase. Purchase from a reputable company like Rogue or EliteFTS. I still have bands from EliteFTS from a decade ago. I have baught cheaper bands that have broke with in a year. These bands are 41" in length. Get a 2" wide, 1.5" wide, a 1" wide and a 1/2" wide. The number of different exercises you can do with bands are to numerous to list. Bands also allow you to overload or add resistance to something like a trap bar if you can't find enough metal weight plates for your liking. 80 dollars.
Wooden Box. A box that is 20x24x30" is pretty versatile. Step ups of various heights. Seated movements. Bench. Sled on carpet. All kinds of body weight movements. Can attach bands around it for leg variations. If you can find a craftsman to build one for you, probably under 50 dollars. Online about 120 dollars.
PVC Pipes. 2 six foot poles can create an imaginative way to stretch or do mobility style movements. You can attach bands to the PVC to recreate additional ways to lift. 10 dollars.
Foam Roller. Outside of being able to roll out quads, calfs and upper back. Can do some calf/hamstring exercises and ab exercises. Can replace the ab wheel. 10 dollars.
Back Pack: This becomes an easy way to add weight to body weight movements. It can serve as a makeshift kettlebell with great results. Can be used for Rucking. Fill it with bags of sand or pea gravel. Can easily make a bag from 10-60 pounds.
BONUS: This is more thoughts on cardio. If you hate it, but know you need it, look for a fan bike. Some deals on craigslist can still be had. A brand new one runs 650 dollars. A friend just sold an old one for 150. It can be max effort work with no joint risk. It can slow and steady. Very versatile for the price. Another option is to drop a few hundred buck for a bike trainer and use your own bike or buy a bike. So you have a bike, but also have a way to use it inside. Food for thought. Running is free. Stair sprints, hills sprints, free. Jump rope, simple.
The body doesn't understand the tool. It understands force and load. It can be a metal rusty weight, a bag of sand, an Olympic Standard Bumper plate, it all has the same effect when used well. Even if you belong to a gym, it is always a good idea to have something around for the days when time is limited or you can't make a class. Having 20 min can still do some great work. Once you have your gym, you will realize what a great investment it is.