If the visa is only valid for six months from when it is issued, how do you get 270 days out of it? Once you hit 180 or so days, doesn't it expire? Maybe I'm being dense; if anyone could help me it would be appreciated. Thank you.

Activate the 3rd entry before the expiry date and you will be ok. You will need to get the Visa as close to your departure date though. you may also need to go on your last visa run a few days early.

The visa expiration is the last date you can enter Thailand, not the last date you can stay. So if you enter right before it expires (and you arrived very shortly after the visa was issued), you can get nearly 270 days out of it.

Thanks for all the info I really appreciate it. If I can get 250 days or so out of it I will be very happy.

A visa is only a ticket to enter Thailand. You should get it just prior to your departure since the "validity" will be 6 months. If you make your third entry on or before the "must enter by" date on the visa (expiration) you will get 60 days permission to stay which can be extended for 30 more at immigration. So: 60 + 30 + 60 +30 +60 +30 =270 (almost). You will have to make 2 border runs and three 30 day extensions (1900 baht each).

Thanks again for the great information.