I've been debating setting up some equipment at home because going to a gym has too much activation energy. I'm looking for the least amount of equipment that can enable the most exercise coverage i.e. weight, cardio, muscle groups, etc. It seems that a rowing machine does pretty well, at least better than a treadmill, or one of those Chuck Norris bowflex machines but it's hard to choose from so many options.
I have a full weight bench in my garage...but I almost never use it since getting kettlebells. StrongFirst has some great information about utilizing kettlebells to achieve your goals.
Get a squat rack and a rolling bench! It unlocks many good lifts and is probably the sweet spot on the "exercises per unit of gym equipment" curve. A case for this approach to garage gyms is made in super-detail in [0].
rowing is good, you're right about that. So is sandbags/rucking (goruck is the premier brand). So is kettlebells, but I have no idea who is good for training that.
Key thing is to find something you like doing.
And I'm with you, reducing activation energy makes a big difference in success probability.
You don't need much. You can do a lot with some dumbbells (adjustable ones if you have money, or just the handles with spinlocks and some 1" weight plates if you want to start small) and a pull-up bar. Many dumbbells exercises are best learned lying on the floor so you don't mess up your shoulders/elbows. Later you can get a bench and a bar. I also like resistance bants (the heavy duty round ones with the carabiner clips, not the flat ones; you can get a set for ~$75). Combined with the pull-up bar you will able to do all sorts of useful back exercises.
I work out at home 6 days a week and the total cost of my equipment was under $200. You can find used gear very cheap on craiglist or your local equivalent, especially in the first quarter of the year and after summer, the two times when people tend to give up. Ending of the college term is also good as students dump equipment they don't want to take home. I found my dumbbells (with 100 lbs of plates) lying on the sidewalk a block from where I live the day after Christmas a few years ago, and nearly killed myself carrying them home :)
If you are older and prefer getting into it at home, you need extra patience and attention to safety. When I got those dumbbells I had absolutely no idea what to do, so I tried doing 10 bicep curls with 10 lb each - easy. Next day I did the same with 20lb each, a bit harder but still easy. Next day I did the same with 30lb and seriously messed up the tendons in my left wrist, and it took well over a year to recover and the weights gathered dust under my desk until I decided to give them another go.
You will get regular small injuries with any kind of serious exercise program so you have to pay a lot of attention to your body's signals. Muscle injuries can be quite painful but are also relatively easy to train around, and a stretch or small tear muscle heals in 4-6 weeks. Tendons and ligaments take much longer to heal and grow, and you'll have to get used to both dealing with pain and thinking about the mechanics of exercise so you understand what you did wrong and what you can do safely.
If you want to be able to lift heavy weights then you should use a gym, even if it's only once a week, to learn about safety racks and get advice/assistance. But you can get plenty fit by starting with light weight/resistance and focusing on repetition while you slowly increase the weight over time. One of the pluses of this sort of training is that as you get the hang of it you can vary your routine to work different muscle groups on different days and allow time for recovery while still moving your training forward. You must also take longer rest periods every few months where you give your body a break. If you need the daily routine such that you hate taking breaks, then just cut your weight or reps in half for a week and then ramp back up to your regular weight over another week or two.
