If you don't run into curbs much, you will find that alignments don't need to be done very often. My 245 has 270k mi on it and I have not aligned it since my wife stopped driving it at around 100k miles. When it has manifested steering problems such as a pull, it has always turned out to be rubber bushings. The front tires on it now have about 50k miles on them, and the wear on all tires is uniform, other than my right rear always seems to wear faster than the rest. I suspect the differential favors that tire for some reason.

I have done cars in my garage using variations on both methods described here. It is harder than it sounds. In and earlier carreer, I have also used simple professional rigs, and I have used a sophisticated 'computerized' 4-wheel alignment rig. I have also watched my co-workers use those same professional tools. Few of my co-workers ever took the time to do the job correctly. The service manager used to cuss me for taking too long on jobs, but guess who he wanted when his own car needed work?

After I replaced the rack, struts, and ball joints on my '90 sedan, I tried to set the toe and camber myself in the garage. It still did not feel right, so I took it to a 'chain' tire store for alignment. It happened that I had marked the tops of the strut towers with a felt pen, so I knew the precise location of the camber adjustments. They gave me a printout that showed that both the toe and camber had been changed and brought into spec. Upon inspection, I found that the nuts had not been touched and the felt pen marks were unmoved. He had adjusted only the toe (typical). The printout was fraudulant. I later took the same car to a highly-rated shop in town, and they did EXACTLY THE SAME THING. They figure it is an old junker car, so why waste their time dialing in the camber? They don't have any problem charging full price for the alignment, however.