I think Chaudhary brothers inherited alot from parents and their parents from their parents. Besides those exclusive "sources" from Durbar and PMs (eg Surya Bahadur ?) the inherited wealth must have been a good amount. Still, the reality is that they expanded may be more than 10000 time of what they got from their father.

I think contrary examples could be: bhatbhateni sahu Min Bahadur Gurung, Upendra Mahato, Jiba Lamichhane who expandaned started from zero and without much 'source' (? not sure 100% he hehe, who knows...) they have made what they have today. But, there are stories about Min Bahadur, i dont know if they are true... Infact people have stories for every sucessful person :)