Here in the UK, it’s about 1.5%. That can often be haggled down to 1% if you have an expensive house that’s desirable enough to sell itself. And even that is getting majorly distributed by online agents, who are offering a flat fee service rather than % of property, which can be an enormous saving.
At 6% it seems a market with a huge amount of fat, just asking for a new player to come and disrupt
I'm sure the fee was probably calculated based on the sale price, but the idea of paying 6% of the sale-price is very alien to the UK at least, and I suspect Europe too (though in Finland I've just bought a couple of places, never sold one.)
I do recall that in the two Finnish places I bought my offer also had a penalty clause - if I pulled out for any reason other than "failure to find financing" I had to pay €6,000 or so.
(I wouldn't have made an offer had I not intended to follow-through, but it was still a little scary to imagine having to pay out!)
All kidding aside, yes, the high transaction costs are a real break on speculation in the housing market there.
Most contracts here do have a 10% deposit, but they're usually conditional on finance, building inspections etc. so you have two weeks or so to pull out before it goes unconditional.
It certainly varies by region, but in my area most realtors have been pressured down to 5% by Redfin and other competition. Closing costs (which aren't really percentage based) were between a quarter and half a percent on a $700k home.