benefit must be to the public: no issue where benefits are offered to WHOLE public such as a trust to maintain a museum that is open to all (is fine even if only a small N take advantage of that benefit and even if location means very few people are likely to walk in).
Poverty - trust to relieve poverty amongst named individuals is not charitable however, for 'my family'/ 'my relatives' it is.
Religion - public benefit if either 1. the place of worship is open to all, even if only a small N attend; or 2. whilst not open to all, members of the relevant congregation 'live in this world and mix with their fellow citizens'.
Advancement of education and other charitable purposes - must not be numerically negligible amount, and must overcome 1. the personal nexus test (ie people linked by a relationship to a particular individual or company are not sufficient- family and common employment normally fall foul of this) and 2. 'class within a class' test- class can be limited so long as those limits are legitimate, proportionate, rational or justifiable given the nature of the charitable trust- cannot be arbitrary and 3. must not exclude the poor- can charge fees so long as profits are ploughed back into the charitable purpose. but if fees are so high that they can only be met by richer members of society, this is likely to affect its charitable status.