I'm an experienced Java developer, my English is very good (apart from a slight Slavic accent) and I've worked as an online tutor before.
I estimate that the lectures would take 10-15 hours taking into account clarifications, going over some things multiple times etc, so I think this is a fair bid in terms of cost.
The time in which we can complete the course depends mostly on you. I'm usualy available for at least 2-3 hours a day and my time zone is GMT+1.
Feel free to take a look at my profile or contact me via PM for any additional details.
Thanks,
Nikola