Earlier quoted context omitted.
* Also UK focused - Matched Betting. Exploiting Bookmakers signup/recurring offers for a guaranteed profit. This is good for an early surge of ~£2k followed by a pretty easily achievable £200-£500 per month for <5 hours commitment per week.
Any guides or links to get started on this kind of thing?
There is an upfront time element needed, and then to keep it rolling you'll need to take advantage of reload offers if you want a trickle, but if you're prepared to put the work in and use a site like this that does most of the "thinking" for you, it can work.