Technically speaking , many European countries already have "Basic Income". ( France , Sweden , Norway...) They are reserved for individuals "Not Active" though ( Unemployed and not looking for a Job ) over a certain age. Those "BI" massively lower poverty , which usually massively reduce crime-rate , drugs related usage etc... With 700€/Month you aren't gonna far anyway, you have enaugh for food and rent , and that'…
Maybe this would actually be a better implementation. Rather than pouring resources into deciding who qualifies for BI you could just establish "havens" for people who cannot or will not work within the current system. The only qualification then is to move to that haven after which you will be provided with a place to live, an optional job, food, clothing, etc. but limited to only what's necessary. Essentially establishing small scale communes within the larger body of a capitalist nation. It could provide an escape for people who don't want to partake in the rat race and just want to exist quietly and pursue their own interests while living spartan lifestyles. You could even go the other way and provide other special zones for unfettered capitalism with 0 taxes and no publicly funded institutions. As long as people can choose where they want to live and can leave when it no longer suits them I don't see why this couldn't work to some degree.