This depends heavily on the market at the time, since there are pressures from multiple directions.
All else being equal, 6% of a higher price beats 6% of a lower price. But 6% of a lower price today in exchange for an hour of work beats $0 if the buyer walks and is not so easily replaced, and it might even beat 6% of a higher price if the higher price comes after many additional hours of work.
Over a long enough timeframe, the trend is toward higher prices, but it's not clear how much of a factor agents are in that, compared to many other factors.
> Over a long enough timeframe, the trend is toward higher prices, but it's not clear how much of a factor agents are in that, compared to many other factors.
I can't imagine agents would have much of an impact when compared to other causes of rising house prices. The way I see it, is that they are more of a kind of facilitator to increase the efficiency of the market, and don't have as much of a role in market behavior.
There is a half-open set of prices the buyer will pay: [0..max).
There is a half-open set of prices the seller will accept: (min..$\infty$]
If these sets do not intersect, there's no deal no matter what the agents do.
If the sets do intersect, the agents collude to ensure that the sale closes at the HIGHEST price in the intersection.
That is why realtors are such a big factor in the housing crisis. They collude to push all of the transactional surplus to the seller, because both agents work for the seller.
All else being equal, 6% of a higher price beats 6% of a lower price. But 6% of a lower price today in exchange for an hour of work beats $0 if the buyer walks and is not so easily replaced, and it might even beat 6% of a higher price if the higher price comes after many additional hours of work.
Over a long enough timeframe, the trend is toward higher prices, but it's not clear how much of a factor agents are in that, compared to many other factors.