Starrett Corp. has completed the disposition of a block of 146 residential condominiums to Meadow Partners in a $61.3 million sale. The assemblage is located on the Upper West Side in the 229 unit rent-regulated Axton building at 733 Amsterdam Avenue. The sales price was a 40 percent discount from what the seller was seeking last year for the assets. The deal was completed with the buyer receiving a $55 million mortgage provided by Mack Real Estate Credit Strategies.