Or should I find a co-founder with programming skills to work with? Any more tips?
I'm familiar with Wordpress and some e-commerce back-ends like Magento, etc. I think I could build it with these, but I got advice not to do this as it will be hard to scale in the future. Should I listen to them?
I think you got bad advice. WordPress can scale very well and if you ever reach a point where you're doing so much business that the hosting platform can't handle it, that's what we call a "good problem to have."
Building any business is going to depend upon a LOT of factors besides the technology. Out of the gate, I recommend that you use a simple, flexible CMS like WordPress to get cash flowing in, prove your concept, perfect your marketing and then worry about scaling.
If you are doing e-commerce I would suggest Magento since you have worked with it. It's an amazing e-commerce platform and stronger then any Wordpress plugin's. You can also find templates available to customize / learn from as you implement your own design. It's PHP/mySql so you can host it pretty much anywhere.
Scaling... I agree with JonDiPietro, and wouldn't take any more advice from that source.
Build it, prove your concept, and if 'scaling' becomes an issue then solve it. But 99.999% of the time no one needs to worry about it and it can be solved with more money thrown at hosting ;)
I'm surprised noone recommended this, but why not just man up and learn to code the tiny bit necessary to "bring up user profiles"? Once you know SQL and basic PHP control structures, that's all you need. The rest is design.
Even if you're not going to code yourself, there's still a ton of value (from a technical standpoint) to having a static site. You can give the programmer the static site and he can just inject it with bits of dtabase calls, etc. in order to make it dynamic. In fact, that's a huge relief as a programmer, since it keeps them from having to really write GUI code, which every programmer hates to do.
So either way, make a static site; but seriously consider reading a basic PHP tutorial and a basic MySQL tutorial to learn how to do "SELECT * FROM users WHERE name='tim'"