Your question leaves lots of things unspecified. For example:

1. How many items are to be considered?

   For a low number of items, a simple exhaustive search runs quickly enough:

   #! perl -slw
   use strict;
   use Data::Dump qw[ pp ];
   use Algorithm::Combinatorics qw[ variations variations_with_repetition
   + ];
   use List::Util qw[ sum ];
   
   my %objects = map{ shift @$_ => $_ } map[ split ], <DATA>;
   
   pp \%objects;
   
   my $iter = variations( [ keys %objects ], 3 );
   
   my( $bestValue, @bestSet ) = 0;
   
   while( my $set = $iter->next ) {
       my $cost = sum( map{ $objects{ $_ }[0] } @$set );
       if( $cost <= 25 ) {
           my $value = sum( map{ $objects{ $_ }[ 1 ] } @$set );
           if( $value >= $bestValue ) {
               $bestValue = $value;
               @bestSet = @$set;
               print "[@$set] => cost:$cost value:$value";
           }
       }
   }
   
   print "Best: @bestSet => $bestValue";
   
   #object  cost($)  value
   __DATA__
   A       6        16
   B       7        14
   C       8        19
   D       8        17
   E       10       20
   [download]

   Outputs:

   C:\test>1147022.pl
   { A => [6, 16], B => [7, 14], C => [8, 19], D => [8, 17], E => [10, 20
   +] }
   
   [A D C] => cost:22 value:52
   [A D E] => cost:24 value:53
   [A C E] => cost:24 value:55
   [A E C] => cost:24 value:55
   [C A E] => cost:24 value:55
   [C E A] => cost:24 value:55
   [E A C] => cost:24 value:55
   [E C A] => cost:24 value:55
   Best: E C A => 55
   [download]

   But for large numbers of items, this exhaustive search could take a very long time.

2. How do you determine "best value"?

   Looking at the results above there are several ways of getting $55 worth of goods for $24 outlay; but they result in a 'profit' of 229%.

   However, for $22 outlay, you can get $52 worth of value resulting in a 236% 'markup'.

3. You don't state whether you can purchase multiples of a given item?

   If you can, then switching from variations() to variations_with_repetition() gives a different set of results:

   C:\test>1147022.pl
   { A => [6, 16], B => [7, 14], C => [8, 19], D => [8, 17], E => [10, 20
   +] }
   
   [A A A] => cost:18 value:48
   [A A D] => cost:20 value:49
   [A A C] => cost:20 value:51
   [A A E] => cost:22 value:52
   [A D C] => cost:22 value:52
   [A D E] => cost:24 value:53
   [A C C] => cost:22 value:54
   [A C E] => cost:24 value:55
   [A E C] => cost:24 value:55
   [D C C] => cost:24 value:55
   [C A E] => cost:24 value:55
   [C D C] => cost:24 value:55
   [C C D] => cost:24 value:55
   [C C C] => cost:24 value:57
   Best: C C C => 57
   [download]

   And a different 'winner'.

You need to clarify your problem description.

Also, on the basis of previous experience of answering questions here; "simplifying" the problem description nearly always results in wasting a lot of people's time because they solve the problem you've described in a way that isn't applicable to the real problem. It's nearly always a false policy.