What free tools are available

When you do Market research about starting new business, and competitors analysis, their prices, current trends, and reports / trends to see whether is your service needed, what tools are you using?

I ll be researching keyword trends, forums, ask target audience what they need or willing to pay for, but not sure what tools ( if possible free or free trial) and there and what reports to seek? Because market moves fast, so report made 6 months ago maybe old. Are there any prediction trends available to read for free?