To answer the last two questions. @Railrunnin, I mostly use manufactured decals. Mostly Microscale, but also Hearld King (now out of business), Rail Graphics (also out of business), Industrial Models (not doing decals any longer) and Shell Scale. I do want to give the Tichy Train Group decals a try... they've got a pretty good selection.
Again, an advantage of redoing smaller cars like I am, is the ability to take advantage of HO decal sets made for larger rolling stock or locomotives. Some of the HO decals are just too small even for 027 items.
I think the color saturation on screen printed decals is the best. I have tried to use a laser jet, using the blank Microscale stock, but never had good results with that. I've since read that a special blank decal film is made by some companies especially for laser jet printers. But you still cannot do white lettering, unless you use white decal stock and print the background color around it... no easy task to get a computer printer to perfectly match a paint color, other than black. There are a whole bunch of various videos on YouTube about printing your own decals on a laser jet, the pros and the cons.
The yellow Conrail caboose on the first page of this thread, I did make the decals on a copy machine, using Microscale blank stock. I couldn't find a large enough CR logo in black. I printed out what I wanted on blank paper and then taped the Microscale stock directly over the printed area on the paper, making sure I was feeding the paper thru the machine the correct side up. I also did this when the machine was first turned on, to avoid any melting damage to the copy machine.
The Looney Toons circus car on the first page also, had color decals I had made for me, along with black decals I again printed on a commercial Xerox type machine.
@Jeff_the_Coaster_Guy, Yes that is correct. Decals won't adhere well to anything but I gloss surface. When I can, I use gloss paint. Sometimes the color I want is in a matt or satin finish, so then I put a coat or two of gloss on after the painting is done. I'm using spray cans, so it pays to be flexible. I've used this rust colored primer that is pretty darn close to a Tuscan red color. So there's an example of having to gloss coat after painting. After decaling and any detail painting is done, then I put on a couple coats of a flat clear non-yellowing finish.
