This was rehashed on another thread, thought I'd maybe start another one on the subject. First of all, I've bought many used handguns over the years. First of all, the price must be right!.
Name brand M1911s, Colt, Ruger, S&W for example, are really very simple handguns. Most folks can dissassemble and reassemble blindfolded. Parts are readily available and simple to change out. I've no experience with the Berretta, but it, too, looks pretty simple.
Single action revolvers are easily fixed, and parts are also readily available. And they just beg for custom touches. My latest has been a used Uberti Flat Top .45 Colt, bought at a good price and replaced parts I did not like fairly easily, and even sold the take-off parts.
Very few guns are broken beyond repair. And a good second hand gun can be turned into a gem. My daily carry gun, a Ruger .44 Special Blackhawk, started out life as a .357 Magnum.