No,you dont need to sell a house just to invest or buy bitcoin.If you ate a wiser kind of a person,you dont need to do that..because bitcoin dont need anything,just trust on it and if it is your decission to buy a coin,that is not a bitcoin fault.It is up to those who wants.But if I am yours,you dont need to sell your house just for bitcoin,dont take a risk of it so that you will not regret someday.Just do what is the better way and think harder before you do.