Offers and discounts are provided by the brand and it may also vary according to the city, brand, and model. Click on the link to check the current month offers (if any): link
There are scenarios wherein dealers also give attractive deals to their customers. Click on the link to check dealership details: Car Showrooms
The difference between Volkswagen Polo TSI and GT Line is that TSI comes with the turbocharged engine whereas the GT Line comes with the direct ingecto petrol engine and the difference of the feature are also there like rear AC vents, 4 airbags ect are available in TSI variant which are not available in GT Line. Moreover, you can click on the link@https://www.cardekho.com/compare/volkswagen-polo-and-volkswagen-polo.htm] to see complete comparison.
The resale value of a car would depend on certain factors like
brand, model, physical condition, kilometers driven, no. of owners, accidental history, and many more.
Volkswagen is a well-known brand so if your car is duly serviced and maintained well then you will get a
good resale value.