Is there any cost associated with data uploading via Data Sources. If yes then what is the cost
No Special Cost, All you need is an AEM login and FTP get enabled.
for more information please ref below links
Upload a Data Sources file
How Data Sources works
Andrey Osadchuk, actually there is only one type of Data Sources that has cost associated - Full Processing Data Sources. All others are free.
Any line uploaded to Analytics via Data Sources FTP is considered a server call, so the cost will be calculated accordingly.
Thanks Balaji for the help