I think the answer for the OP is it all depends on date/time/location.
Last week I was looking to book a Premier Inn in London for July and they wanted upwards of £150. That time of year tourists and tour groups take block bookings, so remaining prices rise, so I've had a re-think.
The other option is the Travelodge or Premier Inn saver rate, but you cant get a refund if the WG or punter cancels. Cheap hotels in big cities are getting like rocking horse droppings. Three or my last four punts have been incalls to the girl's flat or rented apartment, when once I was nearly always a hotel man.
Lastminute.com may have 'secret' hotels but I like to know where I'll be, exactly how far from public transport and how easy access for the WG is.
Every town has small private hotels but seldom suitable for punting, and there's cheap ones, but you risk bed bugs!