Basically:
High tax ( $700,000 on average)
Maintenance ,upkeep bills are much more expensive.
Cleaning: who is going to clean huge windows ..so cost of hiring someone to do it goes up.
Heating/cooling the home costs are higher.
Most winners do not stay more than one year due to the additional expenses.
Knew a young man who won a Dream Home on the west coast of Canada and a year later
he returned to visit his family and told me that without the extra $25000 that he also received
he would not had been able to foot the bills incurred from living in it.
Thus he stated that is why they also give a Cash prize.
He used all of the cash prize to pay the upkeep for six months until he could sell the home.
He finally at the last week sold it and turned that money from the sale into a local Business of
his own. ( Restaurant : Jasper Brewing Company) and its still going strong.
He was only 23 years old but his parents advised him ( they had their own Restaurant too).