A "fix-up" novel (1954) built from 5 stories originally published in Astounding from 1943 to 1946. This is the "Artur Blord" series: all appeared as by E. Mayne Hull (only.) I compared the stories to original sources, and all were noticeably revised for the fix-up. Hull married Van Vogt in 1939 - these probably have some collaborative effort, and the novelization in 1954 probably is mostly Van Vogt's effort, as "fix-ups" were common for him.

The stories:
Competition
The Debt
The Contract
Enter the Professor
Bankruptcy Procedings