I find that Newhaven to Dieppe is normally a cheaper ferry crossing than Dover to Calais. Plus as its ~4 hours you can have a quick Power Nap to refersh you for the rest of the journey.
There are cheap but basic hotels called Formula1s all over France, Think a cheap and cheerful version of TravelInn. All depends on how 'cheap' you want to make it
http://www.hotelformule1.com/formule...e_france.shtml
Theres one halfway from Paris to EuroD, so you could easily catch the metro(RER) either way depending on your mood each day.