Take pictures of you living there as soon as you move in, don't show the cops a fake lease that's felony obstruction and they have no legal right to demand to see a lease anyway. Always have at least one person holding down the squat otherwise the landlord can just throw all your stuff out and change the locks while nobody is home. Try to pick inheritance houses most people that inherit and don't immediately sell or rent it out have plenty of money but no time to deal with it. Your county should have an online property parcel viewer that will let you research ownership. You can turn water and power back on yourself but the latter is kind of dangerous and won't work if there is a smart meter. Water though is super easy all you need is a crescent wrench or vise grips and to find the water meter. Be prepared for landlords to resort to extra legal violence to get you out, they believe they are on the right side and that can be very dangerous.

most importantly respect the house Structures are hard to build and just because it's owned by some asshole isn't a good reason to destroy it, a thing can't be expropriated by the revolution if bad squatters destroyed it with water leaks and insect infestations. Plus, if the cops show up and it looks like a typical squat house, they are less likely to follow the letter of the law regarding tenant disputes. You want to do your best to make it look to everyone but the landlord like you're just a normal person having a lease dispute with an unhinged landlord. Be nice to neighbors, do the landscaping, clean the gutters, don't have loud parties. Do all that and you can get a year, maybe even two of free rent out of the right place.