It's difficult to determine what constitutes a large amount of Bitcoin, as it depends on various factors including the price.One platform that offers OTC trading and sells Bitcoin in large volumes is Hi-Table Cryptocurrencies investment and Bitcoin trading OTC Desk.The definition of a large amount of BTC varies amongst individuals, but generally, it would be valued at $10,000 or more.It is advisable to allocate 5% to 20% of your total investment capital to Bitcoin, depending on your risk tolerance and experience.