The streets between the monastery and the Plaza de la Constitución hold the classic small hotels — several with lonja views. Uphill toward Abantos gets quieter and greener. Near the station (15 minutes downhill) only makes sense for early Cercanías departures.
San Lorenzo de El Escorial lists around 28 bookable hotels and guesthouses, from roughly €54/night. Prices on the area page are live; booking 3–6 weeks out usually lands the best rate, with free cancellation on most rooms.
If it books out or you want to compare: Cercedilla (from €45/night), Navacerrada (from €50/night), Gran Vía (from €48/night) — each with its own area guide on this site.
Curated picks are coming — meanwhile, the live search covers every bookable property at the same price or better.