There's nothing expensive about bitcoin because it renders the a free and convenient opportunity for anyone to get into the market and invest as they could equally afford to, there is no particular rate or amount one must started with, it is convenient to hold without having to incur any maintenance cost for it wallet or use, just as we have in using fiat currencies, whereby they charged us for many things for using the government controlled fiat currency and added no value on our money the way bitcoin does.