I just saw this on a website....would it work for me or would I need something more conventional?

http://www.groworganic.com/cold-frame-gardenstarter-kit.html

Something like that cold frame could work, but you would really need to watch it during the day times. You could end up saving the plants from a night's cold snap only to fry them by noon the next day.

You will need to install an automatic lid opener on your cold frame that lifts the lid when the temperature inside reaches 65 degrees. They are available for around $20 to $25 at big box stores.

Lou

I think that your area is warmer than mine and I have a greenhouse but I never started any seeds there. I only use it for the cold sensitive plants that are in pots.
A better solution would be to start the plants in a spare room or the laundry where the temperature is controlled. Most of what I grow is from seeds, I start them inside and then put them back in the sunny porch, I raise more than 60 seedlings at the time for me and friends.
If you are handy like some of the members that post here, you can install a multiple seed starting space using built in shelves and lights and use it all the year.
Cold frames work better for colder climates than here in my opinion.

Seed starting in a past January

Silvia