What should I say when it rains: should I say "Alhamdulillah (Praise be to Allah)" for this blessing, or "Inna Lillahi wa inna ilayhi raji'un (Indeed we belong to Allah, and indeed to Him we shall return)" because of the fatigue and suffering in cleaning the roof afterwards?

The descent of rain is a great blessing from Allah, and the slight harm associated with it is incomparable to the immense benefit that results from it, as Ibn Al-Qayyim explained that good predominates in existence. It is recommended upon seeing rain to say: "O Allah, [make it] a beneficial downpour," and after it ends: "We have been given rain by the grace of Allah and His mercy." If it increases and there is fear of its harm, one should say: "O Allah, [let it rain] around us and not upon us. O Allah, [let it rain] on the hills, the mountains, the bottoms of the valleys, and the places where trees grow." There is no objection to saying "Indeed, we belong to Allah, and indeed to Him we will return" (Istirja') if one's wealth is afflicted by a calamity, along with reciting these supplications.