If you are wanting to run some kind of commercial endeavour then WordPress is the best choice between WP and Blogger.
Refining that answer a little, you should use WordPress hosted on a server that you are paying for.
Blogger from Google and WordPress.com are both 'hosted' services and both place significant restrictions upon how you can use them, particularly in respect of earning money from the sites.
Both the hosted services are, in effect, holding your content hostage. If they close you down you lose all your work, the writing, promotion, design, the lot.
If you host your own site using WordPress the costs are low. Good hosting from a reputable provider such as Hostgator need cost no more than $8 per month and perhaps less. A domain of your own can be around $10 per year (or less with offers)
These are minimal costs to run your own busienss to enable you to have your own 'asset' in the form of websites that can earn you money under your control.