blood glucose testing equipment

I am looking for in-home blood glucose testing equipment. I went to a drugstore where they had some options for me; but not enough English to explain to me the difference. The price difference was significant, from 3 baht to 25 baht per test. I would appreciate hearing from folks here who can help me in choosing the right item. If it is too specific for the forum, please PM me with your e-mail or telephone #. Thanks in advance.