Brick won't work, if you're going to build a wall, you have to plaster it on the outside, otherwise after ten or twenty years those bricks will loosen.,The old man said, "It depends on how many houses you want to build. Six houses would cost about 40,000, three houses around 20,000. How many houses are you planning to build","Then I'll order 20,000 blue bricks and 20,000 red bricks. Uncle, give me a discount."。