Two men alleged to have used the funds of a fake tradie scam to buy Rolex watches and designer clothes have been busted in Melbourne's east.

Police allege Irish nationals Toby Harris, 29, and Martin McDonagh, 28, are "travelling conmen" who were operating a so-called Irish roof scam to trick vulnerable Melburnians out of hundreds of thousands of dollars.

Two men have been arrested after an investigation into travelling conmen operating a roof scam in Melbourne's east. Credit:Victoria Police

One victim in Melbourne's eastern suburbs lost $260,000, police say.

Acting Inspector Scott Dwyer said travelling conmen mostly door-knocked or letter-dropped homes and businesses to offer fake maintenance and repair work such as asphalting, roof cleaning, tiling, painting or tree lopping.