TEven before the longest bull run ended and the global economy was in decline., Even before the longest bull run ended and the global economy was in decline,

Tthe worldglobal art market had already been losing momentum for a whilsometime. the global art market had already been losing momentum for sometime.

As spending of any sort became deeply unfashionable, more collectors stayed away from galleries and salerooms, which brings aution houses had to pay out a huge deposit. As spending of any sort became deeply unfashionable, more collectors stayed away from galleries and salerooms, which brings aution houses had to pay out a huge deposit.

which brings aution houses had to pay out a huge deposit. I do not know what you mean in this segment. Who is avoiding the "huge deposit?" Auction houses are businesses, but the first have of the sentence seems to imply the ultra wealthy as the Subject.

However, someone buyers have the confidence toin a return, believing that this artperiod is simply a market -slump lies inand merely indicates the lack of good artworks to sellpieces for sale. However, some buyers have the confidence in a return, believing that this period is simply a market-slump and merely indicates the lack of good pieces for sale.