Not only the nosy public, but his children too considered him a man of means. His oldest son, David Tevele Berliner constantly required financial assistance from him. Berliner would later find purpose and stability as a leading figure among the Perushim of Jerusalem, until he was poisoned, perhaps by his own grandsons in 1851. Evidently he supported all 7 of his children in various ways. In Hyman A. Simons' Forty Years a Chief Rabbi he reveals the unfortunate fact that his youngest son, Hirsch, who was a wine dealer in Cracow, was overcharging his father and several wealthy London Jews. Simons cites an 1828 letter to his daughter Fanny (then married to R. Akiva Eger's grandson) asking if she would send him Hungarian wine, because he realized that her brother was overcharging him. Simons says that because of this Hirsch's business collapsed and he moved to - you guess where.
In any case, Hirschel's reputation was that he was extremely wealthy. Certainly a man of means, but like many men of means, he felt that his actual worth was highly exaggerated. In fact he indicated that he was not financially independent, and if it weren't for his expenses he would quit the rabbinate and sit and learn. Simons quotes a letter to his daughter Golda, where he says this explicitly. After advising her concerning some financial matters, he tells her that it is true that when he was young that he had money (!) but he lost it. In fact, it is all because his business failed that he became a rabbi in the first place. He says that he had originally planned to be a wine merchant. He had had several offers of rabbinical positions, but he wanted to support himself. When that didn't work out, he felt that it was God's plan that he become a rabbi. In another letter cited by Simons, the father tells his oldest son that he is not as rich as he thinks he is. He comes close to revealing how much money he actually had:
"I am not a Rothschild, perhaps not a tenth part of a tenth of his money do I possess, not in pounds and not even in thalers."In other words, he doesn't think that he is worth even 1% of what Rothschild is worth! Of course 1% of one of the wealthiest people on the planet's fortune has got to be plenty of money. How much was Rothschild worth? And where did Hirschel get his money from anyway?
I don't know how much stock you should put in this, but here are very fascinating paragraphs in an 1835 magazine called Museum of Foreign Literature, Science and Art. As you can see, the London Rothschild is discussed, and his wealth estimated at seven or eight million pounds sterling. Secondly, it says that Rothschild invests money for Hirschel, at R.'s own risk.
Like you, I was curious how much Rothschild's 7 or 8 million is worth. In today's dollars that is over $1 billion, or as much as $10 billion, by a different measure. Simons says that Hirschel's estate was estimated at £14,000, much of it stocks and railway bonds. A sale generated a further £1400. While that was certainly a lot of money, that is far from 1% of Rothschild's worth.
Here is the first page of Rabbi Solomon Hirschel's will: