Yep. Banning cash would not only nail the cottage or slum and construction industries, it would also net most of the black market. Once you criminalize cash - a few savvy thieves will adopt M-pesa or bitcoin laundering - but the black will gray with the cash trail. Taxes will be paid - which needs no incentive - and GoK could cap amounts due for taxation for Mama Mbogas and shoeshiners. Even persuade the telcos or banks to waive such fees on low transactions. Anything above 1K a day should be taxed. The data of course comes in handy for credit rating, planning and innovative folks will come up with new business serving informal - just as they now serve say the diaspora. Cause remittances are well tracked. Seal the tax loopholes in Kenya and the revenues would more than double.