Seaside, Oregon is a very safe community as a whole and have 2 full service Hospitals within 20 miles. One is in Seaside and the other in Astoria. Rentals are a tad scarce in the summer, but there are some. There are several property mangement companies, Beach Property Management is a very well run outfit. They can be reached at 503 738 9068.
If you have any further questions, don't hesitate to ask. We are a very helpful bunch here on the North Oregon Coast. Best of luck.