All perfect praise be to Allah, The Lord of the Worlds, and may His peace and blessings be upon our Prophet Muhammad and upon all of his family and companions.
Raising dogs for hunting, guarding and other lawful needs is permissible since, the Prophet (PBUH) said (What means):"If somebody keeps a dog that is neither used for farm work nor for guarding the livestock, he will lose one Qirat (of the reward) of his good deeds every day." Moreover, Al-Khatib Al-Shirbini (May Allah have mercy on his soul) said (What means):" It is permissible to keep a dog for hunting or guarding livestock and for farming in addition to raising a puppy for similar purposes." [Mughni Al-Muhtaj 2/342].
As for selling them, Muslim jurists said: " Whoever owns dogs should give them for whomever is in need for them for free." In addition, Shafii scholars permitted the dog owner to take money in return for abandoning it for someone else, so the money will be against abandoning the dog not as a price for it. However, Hanafii scholars permitted buying dogs excluding those prohibited to be kept.
Furthermore, Islam permitted training dogs since, Allah, The Almighty, said (What means): "They ask thee what is lawful to them (as food). Say: lawful unto you are (all) things good and pure: and what ye have taught your trained hunting animals (to catch) in the manner directed to you by Allah. eat what they catch for you, but pronounce the name of Allah over it: and fear Allah. for Allah is swift in taking account." [Al-Mai'dah/4]. Because training them (Dogs) is a basic condition to make the preys that they hunt lawful for their owners. In addition, Al-Imam Al-Shafiee (May Allah have mercy on his soul) said (What means): "A trained dog is that which responds to command, doesn`t eat from hunted prey, and if it did as you trained it then it will become a trained one. Besides, if it killed the prey, it won't eat from it, so its (Prey) master is permitted to eat from it, but if it (Dog) ate from the pray then it won't be considered a trained one." [Al-Oum 2/249]. In conclusion, establishing a kennel to raise and train dogs is a recommended since this is considered an act of kindness since the Prophet (PBUH) said (What means): "A reward is given in connection with every living creature". [Agreed upon]. And Allah knows best.