Existing-home sales, or completed residential real estate transactions for properties including single-family homes, townhouses, condos and co-ops, showed a renewed decline last month.

February’s number of existing-home sales dropped 9.6% to 4.88 million when compared to 5.4 million in January.  Sales were down 2.8% year-over-year as well, from 5.02 million sales in February of 2010. The decline comes after three months of steady gains, with November 2010 through January 2011 demonstrating positive sales growth from 4.64 million transactions to 5.4 million.

Given the tighter credit hurdles potential homebuyers must jump through to acquire mortgages these days, all cash is accounting for more and more home purchases. 33% of February’s existing-home sales were all-cash deals (up from 32% in January and 27% last February) — a record number.

First time homebuyers made 34% of February purchases and investors made 19%. Repeat homebuyers made up a mere 14% of the rest of the market.