Install you will pay for (I don't know what specials the Portland market has right now).
Normal rate on the internet service is 45.95 with cable tv or 55.95 without. That is with renting the modem.
Limited cable (locals + goverment + discovery) is 10-14 bucks a month and Basic cable ( 2 - 99 , TNT, USA, Spike, CNN etc) is around 30-40 a month.
There may be specials in the market happening right now so you would have to call 1-800-COMCAST to see before you move or when you get there.
Splitter may work but they are pretty good at filtering it so... probably not.