Voted Best Answer
Apr 03, 2019 - 08:07 AM
I don't know if you would be eligible for this, but you could become a licensed Microsoft Certified Training (MCT) center, which might give you a break on the licenses. I'm not sure it would be less expensive, or what the rules are for that.
Some people purchase packs of System Builder software. They're discounted somewhat but they are generally restricted to being sold with other hardware. In other words, you're buying the OS for hardware that you will resell. I don't know if that's still the rule, but you could buy a 20-license pack of it and see what the EULA says.
You could purchase the home or premium edition, if it would work for you, rather than professional
Just be aware that OEM copies are perrmanently assigned to the PC, so if a PC dies you can't transfer the OS license to another PC.
You can find upgrades on the Web for much less--I see one for less than $3. These may work, but they are almost certainly not legal--the activation keys may have been part of a corporate buy for which Microsoft typically overprovisions the number of keys, as a favor to the customer so that if they have to reinstall the software in the event of a hard drive failure they don't have to buy another key. Don't buy these. You could fiind that most keys are broken and if you're audited you will be paying full retail price. That can lead to some very unpleasant discussions with management, and you're likely to end up with tire marks from a bus on your back.
Overall, it may be the most expensive, but your best option would be to purchase a Win 10 Pro upgrade through a reseller. That's a volume license, you can reimage all of your PCs efficiently with it. If you add SA to it, you can transfer it to another PC in the event of a failure.