I was checking out calyx institute and I believe they were overcharging their services. 4gcommunity.org is also a reseller of Mobile Citizen which runs on Sprint. You have the option of paying semi-annual ($90.00), quarterly ($48.00), or bi-monthly ($36.00) if yearly($168) does not work for you. I'm not a hundred percent sure of the qualifications but they seem to be open to anyone who wants affordable internet. At the very least, I was told families were able to take advantage of this. Essentially, you could be potentially be paying for Unlimited Data at the rate of $14/month. However, I believe you are stuck on the hardware you are given (fuse hotspot). They do not require proof of income. Sprint's service was not good in my area, but 4gcommunity was very detail-oriented in addressing questions!
edit: it seems based on availability you may either get the Netgear Fuse Hotspot or the Franklin R850 Mobile Hotspot.
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