I finished my first harvest a few weeks ago, maybe a month.
I started with a 3x3, but when I was setting it up I realized it wasn't rated to hold my light and carbon filter's weight, so I bought a gorilla lite line 4x4, with the 1-foot height extension. It worked very well and I dunno what I would have done without the extra height. Probably just would have yielded less with less height, I got about 3/4ths of a pound out of 465 watts (cmh and led) on my first run in the 4x4.
along the way I got a 2x4 tent for drying the plants in, and also for use with males and stuff like that. For a time I had my 4x4 flower tent, 3x3, and 2x4 tents all set up next to each other, using the 3x3 for veg with a cmh and the 2x4 for keeping the veg plants I couldn't fit in the 3x3 with some t5s. Just the other day I splurged and got a 5x5 for flower so I made the 4x4 my veg tent. Now I have a 2x4 and 3x3 in the garage. The 2x4 might come out for drying but honestly I think you could flower like 2 or 3 plants at the very very most in either of those sizes. If you can only have one tent, get the biggest you can, I can't even veg a good four plants in a 3x3, since I want to transplant them to 7 gallons before they go into flower, there's not even enough floor space if I have an oscillating fan on a stand.
And also, if space is your only problem and money isn't, buy a gorilla tent, the extra height is so helpful!