FUBella, you need to get over to the West Bay sometime!

Unless I'm missing something, Amtrak does not stop in North Kingstown or East Greenwich, although the railway passes through both of these towns. The train stops in Westerly - Kingston - and then Providence.

For summer/winter rentals, I would propose Narragansett. It has good summer rental potential and then the college population for the school year (URI). Wickford doesn't have much vacation rental potential. South County beaches are a possibility too. Either near Wakefield or down in Westerly. These are my suggestions.

Of course, Newport and the surrounding area are great too.

Jamestown is an island you might consider - but I know that real estate is quite expensive there.

I don't think Warwick is what you're looking for, based on your original post.