We recommend a portion size of 70-120g per person depending on when you are eating the cheese. 70g is ample if you are serving the cheese immediately after a large meal or as part of a buffet. If the cheese is the main part of the meal you will need to allow at least 100g per person and you may prefer to go to 120g if you think your guests will be particularly hungry (or just very fond of cheese!).
However, if you are only a small party, you may find that the pieces look a little small. In this case, choose fewer pieces, or even just one cheese, so that you can present your guests with something that looks more substantial. If you want to provide a wider choice of cheeses, just go for slightly larger pieces and enjoy the leftovers yourself the next day.