In 1977 as a Navy E-3 I was hauling in a whopping $457 a month - before taxes. Purchasing a CB750 was absolutely out of the question.
So every time we were back in port San Diego, I'd find out which ships were soon heading out for deployment, and then spend time in their designated motorcycle parking area talking with the riders, finding out which bikes might be for sale cheap. Generally the closer it got to ships movement, the lower the prices would fall. In about 2 years, when I wasn't deployed on Westpac cruises myself, I bought and sold at least 20 different small street legal enduro type bikes. As long as it had a good tag I could ride the wheels off them and still flip it for a profit. I found most were really fun to ride and easy to sell to other sailors since most were pretty cheap. And as long as the tags weren't expired, I never had to pay to register anything. Profit, baby!
I was finally able to afford my first 750 well used - just in time to have to store it (!) as we left to takeover over Flagship duties in Yokosuka Japan.

But it was waiting there for me when I returned apon discharge, and I rode it for years.