I had been trading for about 6 months, about 5 transactions totaling over a thousand dollars USD.
I was buying hard to find parts for my 1971 BSA Thunderbolt Motorcycle and the seller is in England and used BTC to avoid the huge exchange rates.
Suddenly Coinbase decides to close my account and actually stated they thought I was funding Illegal Drug Trading and funding International Terrorism.
When I got hold of them on Twitter after no replied to my emails or phone calls they told me to send them all the invoices and emails to the purchases, the name, address, phone and email of the person I was trading with.
When I refused they froze my funds, $225.00 USD for almost 6 months.
Your better off using https://localbitcoins.com/ no big overhead costs.