bayonets

I bought four bayonets at a gun show and was wondering a little about them. One is an ordinary K98 looking bayonet with a good scabbord and good frog. The blade has grinder marks where someone tried to sharpen it. Other than the grinder marks the blue is good. It is very much like another K98 I have except this one has a swastika engraved in the metal up near the pommel. It also has 2 inspector's stamps where my other bayonet has one. Is the swastika something someone added after issue or were some of them made that way.
Another bayonet looks like it was shortened by grinding off the point. The blood groove runs all the way to the point. I had heard the Americans did this with leftover WWI bayonets so I guess the Germans could have as well. It has Solingen stamped into the blade. The scabbord also looks like it has been shortened and the mouth and belt hook braised back on.
The other two look like dress bayonets. Chrome with black handles. The one I thought might be fake does not have any identification marks on it. The chrome is good except about 1/4 inch from the tip is peeled off but no rust. It has a leather "washer like" ring on the blade. The blade is the same length as the K98 blade.
The other is shorter and the chrome is not in near as good shape but no bad pitting. It has a scabbord with good paint except under the frog. I don't think the frog on this one is original because the scabbord is painted shiney black but the frog is dull like the one's on the K98s. Also the frog does not have a strap on it and no sign there ever was one. Doesn't look like anything was cut off. Someone did cut a slit in the strap and put a short 1/2 or so wide leather strap with a buckle through it. It is brown though.
I realize I may have shown my ignorance by not knowing all the proper terms and names but this is very interesting to me and learning as I go. Thanks and everyone take care.

This thread needs pics.

THe Swastika is undoubtably added later, there are several blades with these added to try to add value and calling them SS. It could also be a homer as well, my Navy MkII from my dad has a swastika on it but from his time as a scout when he did the Indian scout program. The shortened 84/98 woudl be either a homer or possibly Bulgarian as they seemed to convert many after the war for issue. It really does need pictures if you need help on these

Thanks and I'll see if I can get some pictures added. I meant to add about the shortened bayonet it looks like it was parkerized after it was shortened. I'll work on the pics.