What are the best and most enduring types of waqf – ongoing charity – for those with limited and middle incomes, and are there trustworthy religious waqf institutions that can be contributed to by phone or bank transfer?

Waqf (endowment) is the dedication of an asset and the channeling of its usufruct. The best waqf is determined by the need of the beneficiary and the interest of Allah's religion. The more obedient to Allah and beneficial to His religion the waqf is, the more preferable it becomes. Ibn 'Uthaymeen mentioned that prioritizing between building mosques and giving charity to the poor depends on which is more urgently needed, while mosques are distinguished by being an ongoing charity (sadaqah jariyah). Therefore, the questioner should consider what has a greater impact and more benefit, and prioritize those relatives who are in greater need. As for reliable religious institutions, this is not within the purview of this website.