Bidspirit auction | United States - Modern Errors

United States - Modern Errors and Varieties - 1980, Architecture, 15c multicolored, two bottom right corner margins se-tenant blocks of four, different layouts, both with horizontal perforation shifts, resulting in red inscription and value at the top of stamps and at the bottom margins, full OG, NH, VF, a common block is shown for comparison (not included), Est. $200-$250, Scott #1841a var