It depends.

I also start plants early indoors (still learning, so take my advice with a grain of salt), but I work at a hardware store, so the DIY approach is cheaper for me. I use adjustable wire shelving units and, since I have a Worm's Way store nearby, I use 2 of these lights on each shelf: http://www.wormsway.com/en/STSL130 The heat output isn't that bad, so I can just affix them to the wire shelves using velco strips looped around. Also, they can be hooked to one another. You can also use fluorescent lights that you find at any hardware store as well, but I prefer these because they're smaller and more compact. Just get a plug-in timer so that your lights turn on and off at certain times of the day to same electricity.

Greenhouses are nice, but most of the time I've found it's better to use them for getting plants used to being outside. I live a zone a bit north of you (6a) so it may be a different story for you.

Both a light setup and a greenhouse will grow plants and there are pros and cons for each one. I have both. I grow my plants that take a longer time to grow to maturity under lights when it is too cold and would take too much heating to grow in the greenhouse. When I do open up my greenhouse I transfer all my plants to the greenhouse.

Depending on what you use for heat it is probably cheaper to grow under lights on the other hand a greenhouse will hold more plants so if you are only growing a few trays of plants it is better to use lights. The downside is the hardening off and carrying your trays outside and back in.

It is cheaper to set up a light system than a greenhouse. I wouldn't get a ready made grow cart. You can set up a light system for about $100 or less. That's about what mine cost me. My husband built me a set of shelves out of lumber he had laying around and I bought 3 shop lights with T8 daylight fluorescent tubes and a couple of power bars and that's all I needed to get started. I did invest in heat mats and other things later on to optimize germination but things grew well under my light set up as is

If you look around you may be able to find shelves cheap and compare prices of lights.

tanyuu--Those are very expensive lights and they don't have fins to direct the light down so your plants are losing a lot of light. At least half the light is disbursed to the surrounding area instead of being directed down on to your plants. Yours also don't have chains to raise and lower the fixture. You can buy shop light with side fins and chains at Walmart or Home Depot that takes 2 T8 bulbs for less than $20

Yeah, I have a few like that on some shelves. The problem is that I can't really daisy-chain them, so they take up a lot of outlets. I've since put reflective material around the shelves to help direct the light. I'll have to experiment with ways I can put fins on these lights, though, as you bring up a good point.

You don't need to daisy chain any lights and you would be in danger of overloading your outlet if you did. Power bars are made for just such things. like all the plugs on your computer go into a power bar and that is plugged into 1 socket. I have 2 power bars. One for my 3 light fixtures on a timer and one for the heat mats and they are plugged into the 2 sockets on 1 outlet. They have been this way for 3 years now and I haven't tripped a breaker yet.

Good to know! I'm still learning, especially when it comes to lights, so I'm glad you answered this thread too so the OP author would know.

Thanks for the ideas. Maybe I will go to a hardware store and see how to make my own light setup. I just need to find a space where the cat won't get into it! Then maybe get a cheap greenhouse for once the plants sprout up and get big enough.

Kim--If you only want a greenhouse for hardening off I suggest you get a pop up cold frame like this one

http://www.amazon.com/gp/product/B00012D01S/ref=pd_lpo_sbs_dp_ss_1?pf_rd_p=1944687622&pf_rd_s=lpo-top-stripe-1&pf_rd_t=201&pf_rd_i=B0002UVS3G&pf_rd_m=ATVPDKIKX0DER&pf_rd_r=0MTDHZ34SHB8205TR1MZ

I have one that I use for the overflow from my greenhouse. They say it will roll up into the bag that comes with it but I use the bag to store my stakes and the piece of landscape fabric I use as a floor. When I'm finished I fold in the ends and fold it in half and wrap it in a tarp. It goes in the basement alongside my storage cabinet until needed for the next year. It is simple to set up and take down. You do have to open it a little or a lot every day and close it at night. Even on a cloudy day the heat can build up in there enough to fry your plants but then You have to do that with a greenhouse too

Now for my fourth year I am growing hosta seedlings in my basement. I started the first seeds the middle of November and have now 3x3 inch plants. I grow them under 24 hrs fluorescent lights on two shelves in the basement. I use 4ft common fluorescent lights like you can buy at big box stores, suspend them on chains 1 inch above domes of seed trays or plant leaves. I have the seedtrays and lights enclosed with 2 walls and old towels. The heat from fluorescent lights is enough to raise the temperature under plastic domes to close to 80 dgrs, in the area without domes to 71 dgrs in a 60 dgrs basement. This is enough for hostas, so I no longer use heat mats.

I also use cardboard with aluminum foil taped on it standing around the hanging lights and plant trays to reflect any light back to the plants. So I have created grow chambers which I only open once a day to check, if I need to replenish water in the trays. Water contains half-strength Miraclegrow tomato fertilizer.

A former neighbor was an engineering liason to a lighting manufacturer. He said that the benefits of special growing lights are minimal, so he himself used only basic fluorescent lights in growing seedlings.

Here in upstate NY temperatures will be warm enough at the beginning of May to bring my seedlings outside. I will place them in shade and bring them into the garage should temperatures dip below 50 dgrs.