I am hoping to create and licence online versions of SugarCRM. I am planning to customise the code and charge my customers monthly/annually for using it, hosting costs, etc.

Is there anything in GPLv3 which will not allow me to do this? I will not be selling the software to them just allowing online usage, etc. So, I think i dont have to give them the code either.

Please let me know your thoughts on this.