Cost of developer license depend of country region. License has different costs at different regionos. In my country (Serbia), cost is:
*NAV2009:
-Application Builder 5.200$ (+16%BREP)
-Solution Developer 18.200$ (+16%BREP)
-Developer's Toolkit - Source Analyzer 5.200$ (+16%BREP)
-Developer's Toolkit - Compare & Merge 1.300$ (+16%BREP)
*NAV2013:
-Application Builder 7.200$ (+16%BREP)
-Solution Developer 25.200$ (+16%BREP)