GST Invoice Series for different services

Respected members, 

I am registered under GST Delhi as M/s ABC services, (Proprietorship ), providing Security services. 

I also given a property on rent for Commercial uses. So , I want to ask whether I can issue invoice on the same GST Number or I need to get a New GST registration. as Property is on Personal Name. 

And what will be the Invoice series for Rental Services whether it will a new series besided ABC services, or i can use the same invoice series.

Thanks.