My MIL is selling her late brother's house for an asking price of £300k with an agent fee of 1%. All fine so far. However, when she came to sign the contract the agent suggested that as an extra incentive for them to sell it, for every £1000 over £300k, they'll take 10%. I've never heard anything like this. Surely if the fee is 1%, that's what it should be regardless of the price achieved? Does it mean they won't try very hard to sell it if she doesn't accept their proposal? I can't help feeling cynical here and I don't want her to be taken advantage of.