HouseScanner: Discussion About the Assumptions

HouseScanner/HouseReader is implemented based on some assumptions:

The interest rates:
The current interest rate is some 2% to the bank customers. For those who can negotiate, the interest rates are often even lower. My calculations assume 6% before tax deductions. The interest rates has been varying over time, with a long period of an extraordinarily low interest rate. For the time span that I plan to live in the house (some thirty or fourty years), I assume that the interest will converge back to a higher value.

The travel time:
We value the travel time to 3 SEK per minute. That means that we are indifferent between paying 240 (3*2*2*20) SEK extra per month for a house or accept one minute more travel time for both of us per day.

The travel time is based on the shortest time of either bicycle or public transit. I omit the car option, since I fear that the petrol prices will increase over the time span that I've mentioned above.

Me VS My Brain:
One pitfall when looking for houses (or making any decisions at all) is how our brains appear to function. Put simply, the emotional parts of our brains will jump to a conclusion, and the "rational" part of the brain will wake up some seconds later and try to find rational reasons to justify the original conclusion. The Nobel Memorial Price in Economics laureate David Kahneman has written an excellent book about this: Thinking Fast and Slow.

The algoritm that HouseScanner is an attempt for me to confront my self with some numbers on a screen, in case I fall in love with my house. Hopefully, that can help me tell whether it seems to be an expensive home or not.