College Admissions In Kochi

So my sister is preparing for her 12th boards and most of the renowned colleges outside and inside kerala have started their admissions. So in kochi she has planned to join either sacred hearts thevara(SH), ST Teresas[STC] or Rajagiri... As per what i have heard is it hard to get into these colleges under merit seat and a large amount of money has to paid in order to get seat under management qouta? Is it true? If yes how much would these colleges charge?