Can you buy a house with BTC? Yes! All you need is a buyer with coins and a seller that will accept them. The value of the transaction is as of the date of the contract, when the coins change hands.
Yes i believe that you can buy a house using a bitcoin as long you have an enough price of bitcoin to buy your own house and also if the seller accepts bitcoin as a payment. Nowadays people are more delightful if they recieved a bitcoin because it is very valuable like a gold.
In United States, there are lots of real estate company accepting bitcoins for buying houses. It's common in US, I believe. But you need to be careful, because after you gave your bitcoins, the price can go up hard and you miss the chance of getting more money from paid bitcoins.