I recently acquired an S32 model Giuletti recently myself, although mine does not have as fancy a grill (lucky you)! I can tell you, although I'm no "expert" accordionist, and I've just come back to playing, after not playing for 51 years, I like the sound of the instrument, and it suits me fine, because it is lightweight, and I'm still in the process of recovering from a traumatic injury almost a year ago now (fracturing both my elbows). That being said, I don't know if there's much financial value to it, I guess it depends on the condition. I was lucky, in that I brought mine to a repair guy, and he said it really didn't need any work, but might in the future, I think something with the reed valves. I was lucky it was in good shape, because apparently the case was destroyed in a flood in the house of the previous owner (who I did not know). I guess the instrument was not in the case at the time. Anyway, I've seen similar instruments on ebay, where people are asking anything from $800-$1,000. I don't know if they're getting that, but that's what I remember seeing. So I guess it depends, if you're looking to play it, or if you're trying to find out the value of the instrument. If you're looking to play it, see if you like the sound. From what I've heard from people and read, Giuletti was well known for the sound of their instruments. If you're looking to sell it, and trying to find out the value, check ebay for that model, and find one that looks like yours. See what people are asking for it, and if you see any that are sold, see what they sold for. I will try to post some pictures of mine. Keep mind, if you're looking to sell it, consider the condition of your instrument - you may want to have it checked out by a accordion repair person. Good luck - enjoy!!!
Here are pictures of mine: