I heard that one of the big costs for Abhayagiri monastery in the USA, is insurance and health insurance for the monks. The anagarikas have to cover their own insurance, but as soon as someone becomes a novice it is paid for by the monastery. Full insurance in the USA is a big cost.
There is no retirement fund.
In the UK, Canada, NZ, Australia, etc, a fair level of healthcare is offered free by the government, so it's not a burden on the monastery funds or lay supporters. Likewise, if a monk wants to disrobe, in those countries everyone gets a pension. Otherwise a monk can remain a monk till he dies. The monastery and lay community provides him with all the requisites. What need for a retirement fund?
One Canadian monk I knew thought it might be a good idea to get the pension and pay it automatically to some other monastery, so he would help the sangha but not break the rule about handling money. But in the end he found he would have to have a bank account in his name, so he didn't want to go there.
saturated with joy,
you will put an end to suffering and stress.