@Parda3: Yes, I  have personal experience living at Na Uyana. I went there last summer and stayed there for about 3 months. A lay person can be ordained as a monk within 6 months or 1 year unless the candidate wants to postpone ordination due to his personal reasons. If someone wants to join the monastery as a monk, only required money is a plane ticket and few hundred dollar for personal expenses until he becomes a monk (that includes $200 for one year visa, and small other expense such as bus fare, visiting local places etc....your guess is close). After one becomes a monk, the monastery will take care of every needs including visa fees for next year(s), medical expenses etc. For monk, not having money is not the problem but the exact opposite is true (having money is the problem because a monk is not allowed to touch money for any purpose; I had one friend from India who was architect engineer and ordained there last summer. It was so interesting to see his problem/dilemma opposite to the world: World always strives for getting money whereas he was striving for finding the suitable place to dump his remaining money for taking pabajja). Yes it is true: once one is ordained as a Bhikkhu, he could live there indefinitely and the monastery would take care of all his needs. Yes it is also quite true: You need $ 900 + plane tickets to not have to worry about money/legal status anymore in my life. Visa rule is much easier than in paper. Once we go there in a visa, monastery will take care of everything for any extension or any stuff like that. Because monastery is much revered institution in Srilanka and such paper work is much efficient and easier when monastery handles it. You need to mention/ communicate to monastery beforehand about your length of stay if it is more than 3 months (because of different visa procedure of possible future extension). 

That is great. You have made such a lofty goal in life. I deeply respect your volition. Indeed pabajja is rare and most salutary.

I have made a video of Na Uyana to show the infrastructure of the monastery and put it in youtube. I hope you will enjoy.

https://www.youtube.com/watch?v=lNwz0T3JhoU