Group of all the Chemical Engineering Textual Courses, listed as below: 
(these have crisp notes on essential topics, questions with solutions of GATE-CH 1988 to 2025 as interactive web pages with suitable images, and topic-wise tests)
  1. Process Calculations (Rs. 400)
  2. Thermodynamics (Rs. 550) 
  3. Fluid Mechanics (Rs. 450)
  4. Mechanical Operations (Rs. 300)
  5. Heat Transfer (Rs. 450)
  6. Mass Transfer (Rs. 450)
  7. Reaction Engineering (Rs. 450)
  8. Process Control (Rs. 450)
  9. Process Economics (Rs. 350)
  10. Process Equipment Design (Rs. 300)
  11. Chemical Technology (Rs. 300)
  12. Mathematics (Rs. 250)
  13. GATE-CH*
  14. ChE-Tests Bundle (Rs. 2500) 
All the above chemical engineering textual courses are available as a single-bundle for 6 months (Rs. 7,200 3,500)

Price in Indian Rupees:  3,500 (6-months access)
Renewal discount for the existing and past users 30%

List of all the courses and corresponding charges are available in this link.