The aptly named Impulse Buy, bought for a knockdown price of $1000 at the Adelaide yearling sales, gets his chance to take his total prizemoney past $200,000 at Moonee Valley on Saturday.

Trainer Gordon Richards said his wife fancied the horse at the sale two years ago and put in a single bid which was quickly accepted.

That unlikely investment has turned into a return of $187,000 and the four-year-old gelding's form leading up to the City Jeep Compass Handicap (1000m) suggests it can increase that purse.

"My wife liked the look of him and they were struggling to get a bid for him, so she put her hand up at a thousand dollars and they took about two seconds to knock it down to her," Richards said.

"We've always treated him as the poor relation of our two-year-olds but he has always stepped up to the mark."

Impulse Buy showed he had a liking for the tight Moonee Valley track when he won on his only appearance there on June 29, coming from the rear of the field.

He was at Flemington the following month but never made it onto the track after he bolted in the mounting yard, destroying a number of fences as he ran out of control on the members' lawn area.

Luckily he suffered only minor cuts and bruises and was back to winning form the following race at Morphettville on August 3.

Richards said Impulse Buy seems to be a 1000m specialist - five of his six wins have come at that distance - who tends to over-race if there is lack of pace.

"He's better in the shorter races when they go hard in front and he can just sit there off them," he said.

"He is stepping up in class and it will be his toughest race yet.

"You never go to Melbourne to run in an open sprint and expect it to be easy - but we have nothing to lose."