First, this question cuts right across almost every church-run organisation you can think of. Equally, nearly all Christian religious groups that are not Catholic need to face up to this same matter. Though only the 'catholicism' tag has been used, I will answer to that, confident that points will equally apply to non-Catholic groups. This means that I am not trying to single catholicism out, so please don't let anyone think I'm taking a swipe at it. I am not.
Second, what Jesus invited the rich ruler to do was addressed to him, personally, and not to any other individual. Jesus had examined this earnest young man with questions, the answers to which Jesus did not challenge. No doubt, even from his youth, this man had zealously endeavoured to keep those commands. Next, the man pursued his initial request, to know what he had to do to inherit eternal life, by asking, "What do I still lack?"
His motives for coming to Jesus were interesting. Knowing that the Law of God is perfect, he wanted to keep it perfectly, in expectation that THAT would give him the reward of eternal life. Jesus knew that no sinful person could perfectly keep the Law of God, but instead of opening up a theological discussion, he had his finger on the spiritual pulse of this young man, and knew that his love of money was preventing him. Therefore, he gently exposed the sin in his heart - setting great store by money and material possessions - by saying that, if he wanted to be perfect, to sell what he had, give to the poor, and then follow Jesus. Jesus assured him that that would give him treasures in heaven. No more needs to be said about this event with regard to the question.
Does it apply to modern-day church-run organisations? Well, some of those are devoted to doing charitable works, to help the poor. One example is Catholic orphanages / sheltered living for poor women, in India, which came to public attention a few decades ago with one elderly nun who was acclaimed as a wonderful example of humility, and poverty. Public attention caused huge donations to then flood into this charity. All well and good, if that money was devoted to changing peoples' lives for the better, helping them climb out of their poverty. Yet, what if a great deal of that money went straight to the main organisastion, to boost its coffers? There was certainly undeniable service going on. But selling up to help the poor? Or increasing the already fabulous wealth of the main organisation?
This does not touch on the property aspect asked about. Hardly any need, for history testifies to how the main religious organisation started accumulating a business portfolio, to this day. It might be argued by it that that account of the rich young ruler only addresses individuals, and not a religious establishment. Of course, there are lots of other things Jesus said to groups of believers about not going out to spread the gospel with money-bags or changes of clothing. Lovers of money never get off lightly in the Bible. So, the core question is, to what extent does love of money entangle those running religious organisastions?
With wealth comes power, and then corruption isn't long in spiritually killing individuals. (Or literally... a banker under a London bridge?) And it's individuals who need to answer questions, otherwise their deeds will find them out and they will be publicly exposed to shame as those who brought disgrace on the good name of our Lord. This has happened recently, more than once, in some Protestant, charitable organisations, but you do not ask about that. All I will mention is regarding the point about property; "expenses on upkeep and salaries of staff, which they meet out of the revenue from immovable property." In many Protestant, smaller, circles that is mainly met by voluntary donations from those attending those buildings for worship.
To sum up the answer regarding this neat, "Sell up and Serve" phrase: Church-run organisations are made up of myriad individuals. Usually a hierarchy, and although most might be volunteers, serving selflessly (even at cost to themselves), a few at "the top" invariably command high wages, make their living out of a full-time job, and enjoy prestige and perks. Those are the individuals who need to make sure that, before God, they have no love of money or possessions, despite that. Otherwise, Christian conscience should cause them to resign their living, but (frankly) I wouldn't hold my breath waiting, if I were you.
