Very nice buildings Brian.
I to have been experimenting building my own buildings and have for the past six months made quite good progress on some of my creations, why buy when you can build it yourself I say.
I live in Dallas / Texas so the weather can be a bit brutal during the summer. This has been my first year of outdoor model building.
http://littleenglandmodelvillage.weebly.com/index.html
I first create my building out of 10 cm thick of plywood and cut to shape. Using a artists knife, I then coat on the walls with a pre mixed concreate mix called Stucco and you can find this at any Home Depot for about $6. It dries quite quickly (being in Dallas 100f heat I am not suprised) but whilst drying, I then scribe in the brick work. Once dried I sand down and paint.
The roof is actually the shingle you have on your real house. I take a piece, cut in to strips and then scribe the tile on the strip to give a roofing effect. I then stick down using the Stucco which gives it a really strong bind and used to fill in any missing gaps.
So far most of the buildings are standing up to the weather. I am busy building more but always looking to better my techniques.
The only problem I have is trying to get my brick work to be better in detail and look for any suggestions on how to make it look more 'building like'.
The other thing I could use is to find a good supplier of doors and windows which I make, but again need to be more detailed.
Simon