Here are a few similarities:
Karan comes to the Goradia House as their saviour – in the movie, Ajay comes to Madan Chopra's house as the son he never had, and impresses him.
Karan's mother does not recognize him because she is unwell – Ajay's mother is unwell in the movie.
Karan's mother begs the Goradias to clear her husband's name of all allegations, made by his employers, and she is insulted – Ajay's mother begs her husband's employers to clear his name, and is insulted.Karan, as a child swears to avenge all the humiliation – Ajay swears revenge as a child, at his father's pyre.
Karan's aim to seize the Goradia property – Ajay wants his father's property back.
Karan pretends to be in love with the main girl, Lakshmi – Ajay takes a longer route, pretending to be in love with the elder sister first.
Karan does not have any feelings for Lakshmi – Ajay falls for Priya.
Karan tortures Lakshmi – Ajay never hurt Priya.
And, we cannot overlook the fact that 'Baazigar' itself was a lift from a Hollywood movie. Life is like the movies. -(SAMPURN)