Home dyeing is cheap and easy. The only trouble I encountered was the couple of times when I actually paid to have it done. I went through a platinum blonde phase in high school and went to an Astor Place salon to have it done once and I had little painful scabs all over my scalp and I looked like an albino.
My natural hair color is fairly close to the color I dye it too which is why with the Loreal Light Reddish Blonde I got a good result. Even if I missed a few pieces it's okay coz it looks like natural highlights.
Speaking of the platinum blonde phase, my hair was to the middle of my back and had been been bleached for ages when I decided to put temporary black on top of it.

When I washed it the black came out but my hair was stained green and purple (the base colors of black, so a stylist later told me, my hair was so dry and porous the base colors clung to it). I did this while living abroad and when my aunt picked me up at the airport when I returned home she couldn't believe her eyes. Not only did I have long purple, platinum and green hair but I had put on about 10 lbs (I had never been one to gain weight previously or since - the English diet of Cadbury, jacket potatos and Guinness worked it's magic on me) and I had zits all over my normally clear complected face. She still busts me about what a sight I was. Anyway, when I got home I got a bob just so I could get rid of all the dead, discolored hair and I let my natural color grow in. I've been off blonde ever since.