I don't want to shit on DEXA scans or anything like that, but the best measurement for body fat is the mirror.
After that, it's a fat calipers you can get for 6 bucks off Amazon to make sure you're headed in the right direction.
Some folks distribute fat differently. I know guys who store a lot of fat around their midsection and they're ripped everywhere else, one of my buddies stores a lot of fat in his arms. It really depends.
I've used this for the last three years and it's served me well.
https://www.amazon.com/gp/product/B000G7...UTF8&psc=1
You don't have to buy it off Amazon either, but I just posted the link.
Other than that, this website works too.
http://www.gymgoal.com/dtool_fat.html
All you need is a tape measure.
According to the website and the calipers, I'm at 15% bodyfat, which also lines up with the picture I posted. Good enough for me.
Other than that, googling the chart of bodyfat percentage will help you as well.
You don't have to spend a boatload of money. If you're lean, you'll fucking know it. You don't need a machine or a $1300 test to tell you that. That money is better spend tinkering with your diet or supplements.