Q.) Are you allowed to increase the price if the seller wants you to, in an auction for example? As far as I know you are not allowed to suggest a higher price if another brother already has fixed the price with the seller. [M.Nawaz]

A.) Sayyidna Anas, Radi-Allahu anhu, reported that Rasulullah once sold a sack and cooking pot through auctioneering. He said, ‘Who will buy this sack and cooking pot?’ A Sahabi, Radi-Allahu anhu, said, ‘I will buy it for one Dirham.’ Rasulullah then said, ‘Who will increase upon that?’ One Sahabi, Radi-Allahu anhu, said, ‘I will buy it for two Dirhams’.

In view of this Hadith, the practice of auctioneering is permissible. (Fathul Mulhim vol.1 pg.326)

And Allah Ta’ala Knows Best