So you'll be leaving in a year but you want the lawn to look nice when it sells. Is that correct? And it would not matter what kind of grass you have as long as it's grass and it's green next summer. Right?

I moved to a new house last summer. With the fortnightly rains we've had from October through mid June, my lawn is all weeds, too. If you keep them mowed, they can fill in and look like this...

It ain't grass but it doesn't look as bad as when I don't mow it. So simply mowing the weeds is one option.

What is your budget? Some grasses grow only from sod (can be expensive if you want an instant lawn) or from seed (which takes time to get established and has other issues). You're in an area where just about any grass will work. Sods you might be interested in include Kentucky bluegrass (full sun only), fescue (sun or shade), St Augustine (sun or shade), or hybrid TIF 419 bermuda (full sun only). Those can be put down now or next spring. As for seed you can use Kentucky bluegrass or fescue for northern grasses or common (not hybrid) bermuda seed for a southern grass. The time to seed the northern grasses would be September for you. The time to seed bermuda would be now while the soil is very warm. Bermuda is a higher maintenance grass either in hybrid or common form.

Are you willing to water the lawn deeply on a weekly basis from the time you apply until it sells? Some people think grass will just grow and survive from rainstorm to rainstorm. It won't. It needs weekly water to look good and keep the weeds out.

Great points. I have bald spots in my lawn. I got a little aggressive with weed killer last year and killed must if the grass but the weeds survived. Would it be better to just plant seed in the bald spots?