very slight variation on the good posts above
Xubia - Hotel Kensington - about 15km
Pontedeume - Pension Casa Apilladeira - about 14km
Mino - Hostal La Terraza - about 10km
Betanzos - Hotel Garellos - about 10km
Stage 5 is the difficult bit - as Al says above, the only midway point accommodation point en route is the Albergue at Presedo. This is small, but most pilgrims walk by it on the way to Hospital de Bruma, so you may have it to yourself, even though it has no private rooms. Either stay there - about 11km from Betanzos, or walk to restaurant Meson Museo nearby and catch a taxi back to Betanzos, thereby enabling you to walk with a day pack one day, or onto Pension Meson de Vento (and stay there 2 nights, if a walk to Buscas is too long).
taxi to Presedo, then walk to Buscas - Casa Rural Dona Maria - about 21km. You may be able to do this after breaking yourself in. If this is too long, when you get to Hospital de Bruma (12km) call a taxi to and stay in Pension Meson de Vento
Sigueiro - Alberge Camino Real (has private, reservable, rooms) - about 17km
Santiago - about 21km