If you have no written lease agreement, you are on a month to month tenancy. You can leave after giving proper/timely notice and the landlord can end the tenancy after giving proper/timely notice.
With that said, I am not certain I understand what you are asking. If you are asking how to avoid eviction, if the landlord is evicting, you have to leave, unless he accepted your monthly rental payment.
If you are asking, can you sue him to fix the house with professionals, the answer would be no. If the place has holes in the ceiling, water and electrical problems and you have no lease agreement, why would you not just move instead of spending time and money and losing a day off work by going to court.
If you are asking if you can sue for the damage to personal property you sustained while living there, the answer is maybe. (I hate those answers too. I like yes or no!) The landlord is responsible to notify you of any latent defects in the property. A latent defect is a "known, hidden danger." It must have been known by the landlord but hidden from you. If you can prove the landlord knew of the holes in the ceiling and that they were leaking AND that you did not, you could recover for any damages you sustained.
A big hole in the ceiling would probably not be hidden, but a small hole hidden by the flue may be. Waterstains on the ceiling and walls may also make the defect known, bringing problems to your case.
Here is another hurdle or problem... your damages are not "replacement" cost but the value of the item damaged. If you had a five year old computer that was water damaged, you do not get what it will cost to replace the computer, you get the fair market value of a five year old computer, assuming you can prove it.
I am sure it is not what you wanted to hear but I hope it is helpful anyway. Good luck.
David Haar, Esq.
Spirakis & Haar, PA
Myrtle Beach, SC
* *This is general advice; please consult with a local attorney about the specifics of your situation as everybody's circumstances vary and laws may differ from jurisdiction to jurisdiction. No attorney client relationship has been formed by the providing of this advice.