This goes well within the 20 year rule, you may want to ask this on a religious oriented sub, such as /r/Catholicism or /r/Christianity.

As an aside, the church can have jobs outside just being a priest. I know my local pastor is also a successful doctor, and a local brotherhood prints and publishes books, though they still use lots of donations.

still it manages to fund every church around the continent? Donations can´t suffice I mean...

I'm not sure that this is an accurate assertion. In many circumstances--such as in the United States--the Vatican does not fund the local churches. Instead the diocese (an organizational subdivision, basically, usually along geographic lines) owns and operates the parishes. There are a thousand exceptions to that basic rule as well, given the multitude of religious orders and groups that are independent of diocesan funding and control. The number of churches owned and operated by the Vatican itself would be dwarfed by the number of churches that would fall outside of that category. Some Catholic institutions like hospitals can be self-funding, as can schools and universities. Parishes can often manage to fund themselves as well via donations and fund-raising, or have saved enough to supplement their income from donations with investments.

Basically, I don't believe that your assumptions about how the Catholic Church is funded are accurate.