I've been building PDF buildings for fantasy gaming, the past year. I started out printing the PDF pages on full-sheet label paper: cut, peel the backing, then apply and burnish to chipboard (for backing pictures/posters/paintings/etc., within a frame -- I pick it up at the local frame shop, in something like 2.5 feet by 3.5 feet sizes).
Unfortunately, the glue on the full-sheet label paper dries out, leading to the printed paper separating from the chipboard. I've switched to using an archival quality glue stick. You can also use archival quality, pH-neutral, PVA Glue (not School Glue, or Elmer's Glue: weak version of PVA Glue, acidic pH, which will damage paper over time, making it brittle, and very fragile to the touch).
Here are some photos of my recent constructs: octagon tower wall sections, warped, but with wooden dowels Hot Glue'd to their interior side to keep them straight; finished octagonal tower; interior of the octagon tower showing wooden dowels employed to keep the walls flat; a group of small houses, which were printed in B&W, then colored with pencils; another group of diverse buildings, including a tower, a barn, and some small houses.
I tried various glues for assembly. I found that for square corners on walls, a square wooden dowel is most effective for creating, and reinforcing the joints. I also learned that Low Temperature Hot Glue is the best method of gluing: it hardens within 1-2 minutes; it adheres to most surfaces, quite well, including HDPE/LDPE plastics, forming a strong bond; it is paintable; it makes a fantastic gap filler; it is easy to work with, and it is relatively inexpensive.
High Temperature Hot Glue has a much longer hardening time, but it is useful in certain situations. I recommend using variable temperature Hot Glue, as well as a High/Low Temperature Glue Gun, which gives you the option to use whichever suits your needs better.
There are colored Hot Glue Sticks available, if desired. Most are for the smaller, High Temperature Glue Guns. But, since clear Hot Glue will take paint well, I usually do not resort to colored Hot Glue Sticks.
The other advantage to using Hot Glue for assembling chipboard buildings, is that it adds weight to the models, such that it will take a pretty strong wind to make them lift off of the gaming table. When constructed with chipboard, and Hot Glue, the models will prove to be quite strong, while being considerably lighter weight than 3D printed models -- and MINIMAL PAINTING IS REQUIRED, typically! ;-) I paint the edges of the cut chipboard black, using an acrylic paint pen, as they work much faster, with far superior coverage, than marker pens. They are available in a wide variety of colors, so you can use them on virtually any terrain piece. Cheers!