Can You Do Hajj More Than Once?
Question

Is it good to do more than one hajj or is it better to do only one hajj?
Praise be to Allah.Can you repeat the obligatory Hajj?
With regard to what is obligatory, Hajj is only required once in a lifetime . Abu Hurayrah said: The Messenger of Allah (peace and blessings of Allah be upon him) addressed us and said: “O people, Allah has enjoined Hajj on you, so perform Hajj.” A man said: “Is it every year, O Messenger of Allah?” He remained silent until (the man) said it three times. Then the Messenger of Allah (peace and blessings of Allah be upon him) said: “If I said yes it would be obligatory and you would not be able to do it.” Then he said: “Be content what I leave with you, for those who came before you were destroyed because they asked too many questions and argued with their Prophets. If I tell you to do something then do as much of it as you can, and if I tell you not to do something then abstain from it.” (Narrated by Muslim, 1337)
Ibn 'Abbas narrated that al-Aqra’ ibn Habis asked the Prophet (peace and blessings of Allah be upon him): “O Messenger of Allah, is Hajj every year or just once?” He said: “It is only once, and whoever does more than that, it is a voluntary (act of worship).” (Narrated by Abu Dawud, 1721; classed as sahih by al-Albani) 
Hadiths on doing Hajj a great deal
With regard to what is preferable, the more a Muslim does of Hajj , the better, even if he can do Hajj every year. There are reports which encourage doing Hajj a great deal, such as the following: 

Abu Hurayrah narrated that the Messenger of Allah (peace and blessings of Allah be upon him) was asked: which deed is best? He said: “Believing in Allah and His Messenger.” He was asked: Then what? He said: “Jihad for the sake of Allah.” He was asked: Then what? He said: “An accepted Hajj.” (Narrated by al-Bukhari, 26; Muslim, 83) 
Abu Hurayrah (may Allah be pleased with him) said: I heard the Messenger of Allah (peace and blessings of Allah be upon him) say: “Whoever does Hajj for the sake of Allah, and does not utter any obscenity or commit any immoral action, will go back (sinless) as on the day his mother bore him.” (Al-Bukhari, 1449; Muslim, 1350) 
‘Abd-Allah ibn Mas’ud said: The Messenger of Allah (peace and blessings of Allah be upon him) said: “Make the Hajj and ‘Umrah follow each other closely, for they remove poverty and sins as the bellows removes the dross of iron, gold and silver, and an accepted Hajj brings no less a reward than Paradise.” (Narrated by al-Tirmidhi, 810; al-Nasai, 2631. Classed as sahih by Shaykh al-Albani in al-Silsilah al-Sahihah, 1200) 

And Allah knows best.