Every business needs an investment to start.
Looking at the costs to open a IB account (example) which is needed later if you decide to trade
a real account - these are near nothing...
You just deposit some amount you do not need elsewhere and start your SIM trading. If you decide
to stop trading just take your deposit out.
As @mattz mentioned - data costs - ANY data.
Just include those costs to the list of fixed monthly costs for computer, internet, power, office etc.
That data cost position will not be the most expensive one in the list!
If you wish to learning about trading and don't mind the type of instrument and brokerage at this stage, you can try MT4 demo platform for spot forex.
1. The data is live (and sometimes 'better' than on a live platform, depending on brokerage) and you can paper trade the main currency pairs for a month.
2. If you wish to open a live account in order to have a demo platform with no monthly expiry, it can be as low as USD300, which is about a tenth of what normal brokerages would require.
3. Most MT4 platforms have the usual indicators and you can find more in forexfactory.com.
1. Most of these MT4 brokers are bucket shops, as spot forex is OTC trading, so each broker is basically a market maker and may trade against you. This is why data on a live account may not be as accurate as that on a demo account as the MT4 broker uses special programs to hunt your stops.
2. The alternative markets provided by MT4 brokers are CFDs, which may not be good trading instruments as they are also OTC.
3. People tend to blow their live accounts time and again because of the lack of understanding of the high leverage in spot forex.
Alternatively, you may wish to open a combine account with topsteptrader. They provide a live demo account with Sierra Chart as one of charting and trading platforms. SC has a sharp learning curve, but once you get the hang of it, it is good.
One instrument can *not* be replaced by another...
If you are used to have invested in the stock market and you wish to trade (intraday or swing) in this market
you might try the futures with leverage and of course higher risk.
One can not find the market behaviour in another market to adapt it to the desired one.
So stick to the instrument you have found great for your trading style or the market you have already got some
There is a learning curve in EVERY instrument - so concentrate.
The more you KNOW YOUR MARKET the easier it is to swim in the bay of big sharks!