Until today, Surface Book with 512GB SSD and Intel Core i7 was the highest configuration people were able to order. But now, Microsoft has added 1TB SSB /Intel Core i7 to its online store. This ultimate device will cost you $3199 and it will ship in 7-8 weeks.
You can pre-order Surface Book from the below links.
|Surface Book||Estimated retail price (USD)|
|Intel® Core™ i5, 128 GB and 8 GB of RAM||$1499|
|Intel® Core™ i5, 256 GB and 8 GB of RAM||$1599|
|Intel® Core™ i5, 256 GB and 8 GB of RAM (dGPU)||$1,899|
|Intel® Core™ i7, 512 GB and 16 GB of RAM (dGPU)||$2,699|