anyways, if your dad is looking for a more economical solution i would recommend the four cylinder, simply because the gas mileage is somewhat better and he will still be getting all of the luxuries, minus the big engine.
However, i own the v6 and i love the power it puts out, so if your dad would like a little burst once in a while, definately the v6.
Also, i would say $22 for the v6 sedan EX- L (non navi) and about $19,500 for the 4 cylinder Ex-L sedan (non-navi)
Personally, i bought a used EX-L V6 Coupe, black on black (non navi)
for $16,500, with only 11,000 miles on it. Came out to $18k with tax and licensing.