Was shaving oneself with a straight razor a common practice, or left to the presumably more skilled barber? When did the safety razor come to be accepted and used by most men? Did the ability to shave one's beard safely without paying a barber lead to a more clean shaven look?
Shaving with a straight razor was common place until the design for the safety razor came out. Think of it like the cartagde razors of today, when they hit the market many men made the switch. The simplest form of hygene would be preferred by the common man.
Regarding having a someone shave for you, its not the cheapest option. Imagine paying the price of a haircut today minus inflation several times a month, it would not be economical.
But it all boils down to personal prefernce, I myself use both a straight razor and a safety razor.
Facial hair trends have changed throughout centuries but during the beginning and mid Victoria Era it was popular to have a beard. The first safety razor was patented in 1880, and Gillette introduced a safety razor with a disposable blade in 1903. Around the same time, people became more aware of germs and bacteria and it became common for hospitals to shave the beards of patients and require nurses to be clean shaven. The US Army also gave every solider a Gillette safety razor during WWI. Gillette also introduced an advertising campaign during this time and by the late 1910's - early 1920's a clean shaven face was considered fashionable and beards and mustaches were considered old fashioned.