Need help please. Is this even legal?

I’ll try to keep this as short as possible. My family has had a business in Bozeman for 45 years since before I was born. My Grandpa started it, passed down to my Dad in 1988. Our family has been in this valley for a loooong time. Unfortunately the opportunity to buy the building had never arose, been renting it this whole time, so I’m sure my Dad has paid for it and some. There’s never been an offer ether. He currently pays $3500 a month, and they demanded he signs a new lease this coming Monday, with an automatic $25% increase. To top it off starting this November owner will make it another 25% increase yearly once November roles around. Basically they’re trying to push us out for good.

This timing comes less than 2 weeks after a new heater had to be installed, and my Dad legit said I bet the rent gets raised or they’ll try to pull some shit. The heater was unsafe, a literal kill hazard, there was carbon monoxide exposure in the building.

My family has busted their asses off keeping this place running and it kills me to see it go down like this. The actual owner of the building resides in California. The property company hated breaking the news to us, but that’s just on the owners request. Not sure what to do, sick to my stomach and lost for words by the amount of greed. We never ask for repairs, never bug them, but we know we’re just a small fish in a big pond when it comes to the kind of money they have.

Just simply looking for advice to give him to try and help. He has until 1pm on Monday they said to sign the lease, and if he doesn’t the vacate process will start. Have contacted numerous lawyers and no luck getting help this short of notice.