These guys are in their late 40's and most things technology related are beyond them, so a techno-geek in his late 20's spouting off the details of what Bitcoin is & how it works probably isn't in my best interest.
Ideally what I want to happen is for them to invest as much as they're willing to risk to put towards building a mining rig with me taking 25% of the profits and I'd maintain the operations out of their warehouse (I'd also have my own mining rig in there dedicated to my profits. Maybe give them 10% since they're paying rent for the place).
Two things. No one in their 40's knows technology in spite of the fact many grew up writing code in assembly on 8 bit processors with 16K of RAM? Adjust your attitude or you won't get any respect if you don't give it.
Secondly, you're going to need to make it worth their while. You want them to buy the equipment and then only give 25% plus you are going to run your own hardware and maybe give them 10%? Meanwhile they are paying the rent and buying equipment for nothing? If you want this to work, you should buy all the equipment, pitch in on rent, and promise them a larger share once the gear is paid off. Otherwise your intentions to use them look pretty obvious.