I'm not sure that the first point makes a ton of sense.  Provided that the ratio of value between the downsized house being sold and the new property being purchase remains equal, an overall increase in the value of housing should put more money in your pocket on a downsizing.  ie. downsizing to a house worth half the value where the average price is $2MM will net $1MM compared to netting $500k where the average is $1MM.