Cheers Hiii priya.. You will start your tour from the cochin 2 day drive to munnar on the way to enjoy some waterfalls and nature beauty 3rd day munnar sight seeing 4 th day thekkady overnight staY 5 th day drive to alleppey stay overnight in alleppey houseboat 6 th day drive trivandrum after reaching in trivandrum local sightseeing
temple visiting,kovalam beach 7 th day drive to kanyakumari after reaching localsight seeing
How you are planning to Reach.. !? One week you can visit Athirapilly water falls just a half day, fort kochi half day, Munnar two to three days, Alleppey one day and Kanyakumari one and half day. If you are flying you can land at Cochin and start your trip and after finishing Kanyakumari you can fly back from Trivandrum. If coming by train also you can follow the same entry and exit and regarding budget it all depends on how many people and mode of transport.