Ok here are my advise trip plan for you.
Jan-21 arrive yangon airport then go to kyaikhtio visit in Bago stay at the kyaikhtio.
Jan-22 back to yangon visit some more place in Bago again
Jan-23 Syrium and yangon sightseeing.
Jan-24 yangon sightseeing then airport depart.for the car price is 430usd(including gasoline road tax with aircon)for the whole trip.
Best Regards