Self-Drive From Bangkok To Khao Yai

[SQ22]

HI SQTalkers,

So I'll be having a one-week holiday in Thailand with the Missus in end-November. Planning to stay a day in Bangkok, then renting a car and driving to Khao Yai (about 3 hours away), where we'll stay for 3 days.

Has anyone done this road trip? How easy and how much is car rental in Bangkok? Can I collect the vehicle in Bangkok but return it at Suvarnabhumi Airport?

Any assistance rendered would be appreciated!