I don’t think having a huge bankroll is the main requirement for successful sports betting. This spreadsheet is more about tracking your performance, so even with smaller stakes, you can still see how effective your strategy is. If you focus on solid bankroll management, you can allocate a certain percentage of your bankroll per bet, maybe let’s say $1 per stake. By the end of the season, if you’re hitting a solid 55% win rate, that should give you the confidence to step up with a bigger bankroll.
I wouldn’t start with a big bankroll either if I’m not confident yet. Confidence is great, but it doesn’t mean much if you haven’t proven anything. That’s why having a track record matters. By "track record," I mean the spreadsheet we’re maintaining, it should show how well your strategy is working.
Once you’ve passed the test and have solid results, that’s the time to step up and gamble with real money. But, of course, it should still be an amount you can afford to lose. Better safe than sorry, right?
Well, all this are basically for those who possibly take gambling/sports betting more serious than it should be, and like I did said in my previous comment here, it's not healthy at all, specially if the gambler is just a passer by like myself.
By passerby, I means someone who is just using gambling as a means or way to have some fun and kill time after a stressful day at work.
I can't imagine myself sitting and updating a gambling spreadsheet on my laptop computer when they are more important and profitable things I should be doing on the same computer..
So, the issue of keeping a betting spreadsheet, bankroll management and all that, simply goes to the professional gamblers, that is those who have choosen gambling and sports betting as a profession.