I'd say don't start seeds now for either tomatoes or peppers. It's too late in the season. The amount of sunlight is decreasing and the plants will take longer to develop as the season progresses. I don't have experience with growing in a green house. Does anyone grow commercially in your area. I'd guess that if you can still find some plants that you could get better results from them. I've read that it's possible to grow tomatoes as a perennial if you could keep them warm enough and provide enough light.