Tip o' the week - watch out for input jacks.
Most of the affordable modern amps use plastic input jacks that are soldered directly to a printed circuitboard. Many of these amps, like the Fender Blues Junior, actually sound great and offer good value for the money, but the input jacks are a real weak link. All it takes to break one is a good hard yank on your mike cable, so always loop the cable through the handle, under the amp, or any other way you can think of to create a "strain relief" for the cord because it sure is easy to trip over a cord on a crowded bandstand!
Skip Simmons