Given the state of things and the rising number of COVID-19 cases (at least here in America), many people are foregoing the gyms (if they're even open) in lieu of doing their workout at home.
If you're like me, you might want to improve upon your setup at home. I built my gym at the end of July or so and figured I'd share some tips that I used to build mine. Because I was looking to build a lifting gym, it's a little skewed towards lifting, but the process can be applied to any gym.
Are you more focused on cardio? Is strength training more in line with what you're looking for? It may seem rather obvious, but some people can tend to just think "I want to get fit, let's get some stuff to help me achieve this goal!" They don't ever think about what they're actually looking to do, what they want to do, and most importantly, what they're actually GOING to do. If you're more of a cardio person, buying and building a power cage probably would end up being a waste of your money and time. Make a list of the things you would like for your gym and make sure you'd use them.
It'd be nice if all of us could have anything we wanted, but with just about everything, sticking with your budget is important. Determine what you're willing to spend and see what is in your list from above that fits within the budget. You can always buy more later.
Look around on Craigslist or Facebook Marketplace to see if anyone has what you're looking for at a reasonable price. Because of COVID, many people are looking for home gym equipment so prices can end up being a little inflated (I found some items in my search with prices raised by 300%), but you can still find some steals. It might be worth checking out what the prices of the equipment are new as well because if the price isn't that much higher, it might be worth it to buy new in case something breaks.
If you're buying something large and need a truck to pick it up and haul it home, Home Depot and Lowes often have trucks you can rent by the hour.
This mostly applies to those looking to purchase barbells, plates, etc., but when building my gym, I found /r/homegym to be very helpful.
Because so many stores are often out of inventory, it can be hard to find what you're looking for. Every Friday, the subreddit starts a new pinned post where users post when the various online shops have items in stock. If you sort by 'NEW' and refresh regularly, you can see when stores drop more inventory and can hopefully pounce.
Many stores also offer to alert you when items come back into stock. You can use these to have them shoot you an email when they restock. The downside to this is that sometimes the inventory is gone by the time you get the email or before it registers that it's back in stock. For ROGUE lifting equipment, someone made a Bot that will message you on Facebook as soon as the site is updated. From a tech perspective, it scrapes the site frequently to see when stock levels change.
One quick note on prices for plates. The ideal price for plates is no more than $2 per pound. Obviously fancier bumper plates will cost more, but if you're just looking for basic iron plates, you don't want to spend much more than $2 per pound.
Those are some of the tips that helped me build my gym. Anyone have any others that I missed?