To buy or not to buy
It's not uncommon for homebuyers to make a purchase based on the blueprint of an apartment. However, this is not ideal as there is no guarantee the paperwork will give an accurate picture of the unit. Those buying a flat in an area they are not familiar with won't have any concept of their building's surroundings - and no amount of online satellite imagery can rectify that.
Nonetheless, there are ways to avoid making an unwise choice. When looking at the plans, consider the overall shape of the unit and its rooms. If the shape is too irregular, for example, it has triangular rooms and many acute corners, then it is not a good option. Rectangular and square units with uniform rooms are preferable.
Note the position of the front door; is there a direct line between it and a window, balcony or bedroom door? If so, say no.
If there are bathrooms attached to the bedrooms, does the door to the en-suite open facing the bed? Will bedroom doors directly face each other? Will the wall against which you place your bed have a stove or toilet on the other side?
If the answer to any of the above is yes, there are fung shui violations that are best avoided and correcting them may require significant effort.