I have been using Buyee for quite some time. Their customer service is good and they also ship out the packages very promptly. There are service fees involved but as they offer coupons every so often it all works out quite well. The only downside is that it takes 1-2 business days for them to make the purchase for some shops and mercari, so the items you are after may become sold out by the time they make the purchase. But Yahoo Auction bids are instantaneous according to my experience.
