Vlookup & addition

Instead of stringing together Vlookups, you could string together SUMIF, like this

=SUMIF($P$103:$P$144,A103,$S$103:$S$144)+SUMIF($T$103:$T$149,A103,$W$104:$W$149)+ ... etc

Seeing that your ranges have a varying number of rows and the value in column A may or may not be present in the range, this will at least not produce errors. Althought it's still ugly ...

In 2007 you could use SUMIFS with multiple arguments

I;d go with Teylyn's approach-I came up with the following:

=sumproduct(--(P104:p170=a135)*(S104:s170))+sumproduct(--(t104:t170=a135)*(w104:w170))+ {etc- repeat this pattern for your entire range)