A Iguana typically lives 15–20 years. Most of what determines whether it gets there is routine care rather than anything dramatic.
Teeth and gut
Both go wrong in these species and both trace back to diet. Constant fibre and chewing material prevent most of it.
Keep the records
Booster schedules run from the original dates, and a new vet asks for the history first.
Balancing calm against independent
Breeds described as both calm and independent need the two managed together rather than separately. With a medium animal that usually means a predictable routine first and training second - the routine is what makes the training stick.
Planning for about 17 years
A Iguana is with you for about 17 years. Budget and routine both need to survive that, including the last quarter of it when a medium animal needs more veterinary attention than it did young.
Exotics vets
Find one before you need one; not all clinics see these species.
What “calm” means day to day
The Iguana is described as calm, independent. Of those, calm is the one that shapes an ordinary day most. It is easy to read as a selling point and harder to live with than the word suggests, because it does not switch off when you are busy.
A breed from Central and South America, living in India
The Iguana was developed in Central and South America. The part that travels badly is rarely temperament - it is the coat and the tolerance for heat. Plan the year around that and most of the rest follows.