@bilalrazzaq
I just purchased my first Prado 2 days back and can share some info with you.
Yes the good ones will cost you more than 20 lakhs. The prices vary alot depending on condition and model, i.e. TX, TX Limited and TZ.
I got a 1996 TX Limited, cost me 19.5 lakhs. It requires the usual maintenance works that include all oils changed and new tyres. The only difference is that TX does not have sunroof and has fabric door panels and seats. My TX Limited has leather interior and comes with sunroof. The TZ will have sunroof, leather interior, dual AC and some with dual fuel tanks (in Colorado models).
Good luck!