Is This Even Legal? Landlord Demanding 25% Of My Business Sale (not In Lease)

I need some advice on a ridiculous situation with my landlord. My family is in the process of selling our pizza restaurant in Connecticut, and when we informed the landlord out of courtesy, they hit us with an outrageous demand—they want 25% of the sale price.

This was never mentioned in our lease agreement. There is no clause stating they’re entitled to any portion of the sale. Yet, when my attorney brought this up, their response was basically, “We don’t care, we still want it.”

This isn’t even the first shady thing they’ve done. When we signed the lease, rent was listed as $5,000/month. Then, when the first bill came, they tacked on an $1,800 ‘common charge’ that was never disclosed. The lease mentioned common charges, but it didn’t specify an amount, so we assumed it was something minor—like $100-$200 a year, not nearly $2K a month.

On top of that, they never maintain the property. The driveway is awful, fences are broken, and they never come to fix anything. Worst landlords ever.

To make things worse, my dad’s lawyer is absolutely useless, and for some reason, my dad refuses to hire a different one. Instead of fighting back properly, this guy just keeps telling us to “work something out” with the landlord. But how do you negotiate when they’re demanding something they have zero right to?

I’m at a loss here. Can a landlord legally pull this? Has anyone dealt with something like this before? Any advice would be greatly appreciated.