A few comments but please bear in mind this is only MHO.
Calpe is quite developed with a lot of high rise apartment and hotel blocks, there is however still a lovely old town. In its favour beaches are great. Predominently a German resort town.
Altea, the main residential area of Altea will be altea hills where million euro + villas abound, views from here are great but it is a bit detached from the town and shops. The old town and church are a treat, beaches mostly large pebble.
Javea, much more diverse in the types of locations and choice of property. There are 3 area to Javea, the main beach area, Arenal, the Port, and the old town. It seems they have come to their senses before overdevelopment happens no new buildings over 3 storeys.
Also consider Moraira and Denia if you want coastal.
Prices as in most places have been under pressure and a deal can certainly be struck however again IMHO the owner of more expensive properties seem less desperate or in such dire need to reduce prices drastically. Where you will find a bargain is not so much by reducing the price making low offers but by finding those properties where people have at last had a realisation about what their property is really worth. Many properties have been listed at the price the vendor considers it to be worth with often many 000’s difference on similar sized villas.