Earlier quoted context omitted.
Why would one even consider entering these markets without the ability to demonstrate alpha over historical results? Yes, your alpha needs to include the ability to beat transaction costs... so if you can't pay for the [relatively exceptionally cheap] cost of several years of your chosen market's historical data, maybe you're not really serious. It's fun to play at being a financier, but let's not pretend that access…
The cost of market data and a system equipped to process it are not inconsiderable. Historical tick data (quotes and trades) for US equities will run you $20k/year, minimum. US equities runs about 30-40GB/day so you are looking at almost 10TB/year. You need to be able to access the data quickly so you probably don't want to compress it and probably do want to duplicate the data, slicing and dicing it in different way…
Not even close, if you consider the alpha for generating value. I know it's awesome on HN to think that generating 10M over 2 years entitles one to a "50M exit."... but that's not the way things work in finance.
20K is nothing... if one thinks it is than one is playing the wrong game.