I've worked as a sales manager, so I'm jumping in with a word of caution. The earning potential of almost all sales position is exaggerated. Some, particularly commission only jobs, are severely exaggerated. For example, after my mostly honest employer was taken over by their biggest competitor, I was told to present a total targeted compensation of ~$44k/year to sales candidates and to avoid stating that it was a commission only position. The reality is that compensation was a draw against commission, and many new reps struggled to earn enough to hold on to their jobs. Those who were successful in my market could expect to earn ~$25-30k. (FWIW, I refused to mislead my employees or potential employees and left the position soon after.)
If he hasn't done so already, I suggest that your husband read through the reviews on glassdoor.com. Are the weekend hours really the only problem? If the reviews check out and he can handle the weekends, then I'd suggest going for it. Sales positions are stressful but so is being underemployed.