I have Evan Designs Model Builder software that I used to create free building models for the website (now defunct) of the model railroad club I used to belong to before I had to move away for work ... I scanned in several unassembled PIKO/Tyco/AHM vintage building kits and modified them significantly to avoid copyright complaints. I found this was the software a lot of card stock building sellers use to create their products. Like santafewillie, I use 65# paper to print out the buildings on my HP OfficeJet printer. A lot of people use Gatorboard to glue their printouts to for the walls to strengthen them from warping ... I just went to Dollar Tree (now Dollar .25 Cent Tree) and got foam poster board. I used colored chalk to cover any white where the walls met. You'll probably laugh, but my family is addicted to Hostess and Little Debbie snack cakes. After they ate all the cakes, I cut the cardstock boxes down and carefully printed roofs on the unprinted side and glued that to my poster board walls. IMHO ... card stock buildings look good in the background or as background flats, but up close they still look like paper craft buildings if they're just 4 flat sides and a flat roof without any 3 dimensional additions to them.