Hi Annie,
I stayed in Manzanares el Real on 3 October and struck a bit of a blip there finding accommodation. I was told by locals that Hotel Parque Real was closed but that you could ring the owner/manager for a room. However, he/she was away on holiday at that time. I don't know about Hostel El Yelmo - I didn't pursue it as I was quite foot-weary at the time and put off by its location ie a bit further out of town and off the Camino. I ended up in a Casa Rural Residencia La Pedriza, which was fairly pricey at 50 euros, but was close to town for seeking dinner and food for the next day, plus was very close to the Camino leaving town.
One option I did consider for this town when planning my Camino (but didn't pursue) was Air BnB - there were at least a couple of rooms offered on this in the town. Could be a possibility.
The town itself is pleasant - helpful bar owners/policemen, and a good sized supermarket.
I walked the Camino de Madrid as far as Villeguillo. My other stays were:
2 Oct Tres Cantos - Hotel VP Tres Cantos - 45 euros, comfortable, very helpful receptionists, have a restaurant that does breakfast starting at 7 am
4 Oct Cercedilla - Hostal La Maya - 36 euros - good
5 Oct - Segovia - Hostal Juan Bravo - 35 euros - good
6 Oct - Ane - albergue (free) - converted school house - basic but clean and quite adequate. Seriously quiet! Didn't see a bar or tienda in the village, although the albergue has a new kitchen bench with microwave.
7 Oct - Nava de la Asuncion - albergue (5 euros) in the polideportivo, note pilgrims are now required to ring a hospitalero rather than pick up the key from Margarita at the bakery. A very warm welcome and quite adequate facilities.
8 Oct Here I headed off to the Camino de Levante via Villeguillo and Olmedo...
Hope this is useful.
Elizabeth