Whether you are designing, buying or renting a home, you need to take in consideration not only the exterior but the interior part of the house as well (i.e., the shape of the house, windows, size of the doors, and rooms).  Avoid irregular shaped houses.  In general, square or rectangular shaped homes are much more conducive to good feng shui than those that have protruding extensions, or which are L-shaped, U-shaped, or wedge-shaped.  Avoid houses with too many corners.  Angles (see figure 1) give off unfortunate Shar Chi and disturbs the chi flow. Poison arrows (figure 2 & 3) such as hospitals, fire departments, cemetery, powerlines should be avoided.  Do not buy or rent a house near these places.  Having these poison arrows next or near your house can cause ill health, loss of opportunities, quarrels, loss of money, etc.

Figure 1

Figure 2

Columns and beams (figure 4) should not be exposed.  Beams, when exposed, hurt the Chi of a family and are obstacle to growth and can cause money loss.  Beds or sofas placed under beams can cause headaches, bad luck and business problems.  If your bedroom have exposed beams, you can buy a canopy bed to solve the problem.

Figure 3

Figure 4

Main entrances of a house is probably one of the most important aspect of making sure you have a house with good feng shui.    Make sure that your front door are not being hit by anything sharp (e.g. pointed trees, neighbor's roof, etc.)  Doors opening one from another is considered bad feng shui--especially if you have three or more doors in a row (figure 5) with one being the back door.  I have this problem with the house I'm renting right now so I closed the back door permanently and put a furniture to block it and I try to keep the second door closed as much as possible.  I did ask my sifu (feng shui master) about it and he told to close the second door. Solid doors are always preferred to see-through doors, and wood is better than glass or steel.  Main doors should look like main doors--the grander the more auspicious.

Figure 5