4P marketing mix will work well if you include 5th P (people) and 6th P (portfolio).
Good sales people will solve fend shui problems instead of condemning. How many houses faces a junction in a housing project? Maybe 2 or 3? Most projects give special price for these unfavorable units and higher price for house no. 8.
How do you solve sloping ceilings? Sloping ceilings in halls is bad only if it is low lying. If it is high, then it is okie. But what about bedrooms? If you can't build a cabinet over it, just install a light trough on the other side to ensure balanced level with the slope.
Even if you want to sleep in it without doing anything, also can. Just put the head of the bed at the higher side of the ceiling. Fend shui said it is bad to sleep with headboard under suppressed ceiling but never say anything with feet under it. You can also paint with contrasting colors to separate the slope and wall.
What about toilets? People say toilets cannot face main door. Bad fend shui. Well, in the olden days in China, all toilets are outside the city and that's why you find people carrying shits at night out of the city. And what do you get? Ching dynasty collapsed and Hong Kong given to British for 100 years. Actually toilets is not recommended to face main door as you do not want smell and sights when you come out of toilets when you have guests at home. Just use a beautiful free standing screen partition. If you can afford it, put up a brick wall.
I am no expert but I do know a little bit supertitions. Happy reading.
I am not going into the topic of feng shui remedies as ASGH14 dont believe in it. Infact, several people especially eco summer / spring buyers have already private message me to discuss on this much earlier. I am most willing to share and advise them. Remember, you must start to believe in it before you do anything to reduce the bad feng shui element in your house.