Kubera's last life on earth was about 7,500 years ago during Dvapara Yuga when the human life-span was about 1,000 years. In this life he was a powerful asura, actually the chief of all asuras. During this life of hatred for Lord Vishnu, as sometimes happens, that hatred suddenly flipped to love. This is similar to what happens at the end of Kali Yuga when ignorance and hatred are at their maximum, then suddenly the times change to Satya Yuga where all is Bliss, love and devotion to God. Kubera's change of heart required that he leave the ranks of the asuras and become a sura and serve Lord Vishnu. To purify his life from all the negative karma brought about from eons of asuric activity, he performed yagnas to all the Grahas and was granted freedom from his karma and attained Brahman Consciousness. Before undertaking his program to attain Moksha and Brahman Consciousness, his physiology was disfigured and dwarf-like. After this transformation, his body took on the beautiful qualities of his Absolute Body, which is how he appears today in the Celestial Realms.
Lord Brahma was so delighted to welcome Kubera into His Celestial Family, that he ordered Vishwakarma, the architect of the devas, to build Kubera a chariot. Vishwakarma conceived and built Pushpak, an aerial chariot which moves of its own accord and which is so large that it can contain a whole city. Kubera would fly in this fantastic chariot and throw down jewels and other precious objects to people on the ground to help them materially so they could devote their time to God Realization.
When Kubera dropped his physical body at the end of his last life on earth, he joined the ranks of the Ascended Masters and was given the task to financially help all those on earth who desired God Realization so they could achieve their objective.
During this last life, Kubera has three famous half-brothers, Ravana, Kumbhakarna and Bivhishana. All three find mention in the Ramayana. Bivhishana was influenced by Kubera and became a devotee of Lord Vishnu, but Ravana and Kumbhakarna were not so intelligent.
It was Ravana, the eldest of Kubera's half-brothers, who stole Pushpak from him and made use of it to further his nefarious activities. The accounts of his misdeeds with the aid of the magic chariot are amply narrated in the Ramayana. First, Ravana abducted Sita, Rama's wife, from her cottage in a forest to his capital in Lanka where he held her captive. When Rama attacked Lanka to rescue his wife, Ravana used Pushpak to parry Rama's forays until Rama, Vishnu's seventh incarnation, at last overcame the evil king's forces and used Kubera's magic chariot to transport himself with his wife back to his kingdom in Ayodhya. After that the fantastic contraption was back in the hands of Kubera who again began going about his usual business of consolidating the wealth of the worlds.
The tale of how Ravana and his other two brothers were conceived is also an interesting story. The fabulous city of Lanka was built by Vishwakarma and the Rakshasas managed to overtake it. For some reason or another, the Rakshasas annoyed Vishnu who decided to attack the city. The evil ones fled because, although Lanka was the best fortified and richest city in the world at that time, they feared that it was still not safe enough against an attack by Vishnu.
At this time Kubera took over the ghost city and settled there with his own attendants. This was not for long for as soon as Vishnu was pacified, the Rakshasas became determined to get their city back from Kubera. They sent a beautiful maiden to seduce Kubera's father. She succeeded and from their union was born the three half-brothers of Kubera. Ravana, like quite a few notorious Rakshasas before and after him, performed stringent austerities which earned him the boon of invincibility from Shiva. With this boon he ultimately defeated his own half-brother Kubera and got back the city of Lanka for his people, the Rakshasas.
After the loss of this luxurious asset Kubera approached Vishwakarma with the request of creating a residence for him. Vishwakarma conceived for him a palace on Mount Kailash, in the Himalayas. The opulent palace was an appropriate abode for Kubera as it was in the north, the portion of the globe of which he was the guardian. Of course, as guardian of the treasures of the devas and the nine Nidhis, special treasures of immense significance, Kubera had for himself the most splendid city in the universe on Mount Mandara, a mountain in Kailasa. Within this city, Alakapuri, is the most beautiful garden in the universe, Chaitraratha. Both are a part of the many sybaritic possessions of Kubera. Kubera is assisted in his duties by his shaktis, the Kinnaras.
All of the wealth that Kubera freely distributes to those who perform his special yagna is obtained from Maha Lakshmi, the Originator of all Wealth in the universe. Maha Lakshmi lives outside all the universes in Dvaraka, an area of Goloka that is opulent with trillions of vast palaces. In each palace lives Maha Lakshmi as the Queen of the palace and the wife of Krishna. In Her Absolute Body form, Maha Lakshmi has 2 arms as do all of the citizens of Goloka. When you see Divine Beings with 2 arms, such as Mahalakshmi, Radha, and Krishna, this indicates they are original, Absolute forms of the Divine that exist outside of all universes in the Absolute region of Goloka. When Mahalakshmi projects into individual universes, She takes a beautiful 4-armed form to indicate that this is one of Her Expansions.
In the picture below, we see Mahalakshmi. The Divine Light around Her head also indicates She is a Divine Absolute Being, and around Her are many stars, symbolic of Goloka. She is showering wealth in the form of gold coins into our universe for distribution by Kubera and his shaktis (called kinnaris). His wife and principal shakti, Kauberi is pictured at his left side.