I can't imagine they'd get past the farmhouse portion.. if even that in the first season. I'm sure the first season will close with his son killing his partner and leave it at that, with the next season ( which I hope to god happens ) picking up with them taking off, finding the housing complex, and wandering around aimlessly and without food until they find the farm. Excellent cliffhangers and 18-24 more issues further out to catch up to. The whole farm and migration to the prison is another season, and the drama with the town across from the prison with the President could be two whole seasons.
I can't imagine a lack of plot right from the comic allowing an overlap by any means. Especially with all the subplots and story arcs within each main arc to cover and flesh out. I think they can have a fairly aggressive pace and not have to worry about too much. I'm assuming each episode is an hour long?