Do you want the best results possible or not? Best results will come from lifting free weights all you need is a bar some weights and a rack to get really good results. Probably need a bench too. You could probably get some results from the bowflex but I'm sure you might want more results than what you can attain using some type of machine
I'll add to this as I train out of my home. I started with the basics:
-a place to lift (built my own lifting platform from plywood and horse stall mats).
-a GOOD barbell.
-a ****-ton of plates. Bumpers if you can afford it mixed in with some cheap Craigslist iron.
-solid squat rack or power cage preferably with a pull-up bar so you don't need to install one separately.
That's about it to get some nasty results. You can squat, pull, press, row, and curl to your hearts content and backfill your program with body weight movements. Afterwards you can add more "toys":
-gymnastic rings.
-dip belt/neck harness.
-strength bands.
-EZ bar.
-landmine post unit (this thing is awesome!).
-more weights!!!
I can guaran-****ing-tee you that you can get jacked with this. And it's not as expensive as it sounds. Just get the most important stuff first and buy what you NEED before what you WANT. Just last week I was searching CL and found an almost brand new Rogue Monster Squat Stand with all the bells and whistles for half the price what their website is selling it for!...oh and it came with a Rogue barbell too!!!
I've learned that machines are nice but not necessary. Look at dudes from the early 40's and 50's like Reg Park and John Grimek. Jacked, lean, and strong as bulls. In fact look at guys in prison! Poor caloric meals, only an hour in the yard, rusty free weights IF they have access to weights at all, and the threat of being manhandled while taking a shower. Yet some dudes get freakin beastly!
And as far as the whole machines vs. free weights debate - most of those guys and gals built up a solid foundation using the basics before putting on the finishing touches with isolation machines. I've actually gotten bigger and leaner since training out of my basement because I'm less prone to dick around with useless ****. I'll still hit the gym once about every two weeks with my one buddy but the funny thing is besides dumbbell rows and chest presses and maybe the occasional seated row machine or dumbbell curl I don't really do anything differently than what I do when I train at home. And guys are always asking what my training is like, haha! Uh...working my ass off?! 80/20 bro. Don't lose sight of the BIG picture.