I hope the company at least knows SEO?

But in answer to your question, I would opt for a template coded with CSS. Those are the most SEO friendly.

Your Best solution is to learn how to do it yourself. Even if you don't actually do it yourself, you will be much more knowledgeable when it comes to hiring someone and getting what you really want.

Good Luck!

There are certainly sites out there made from templates that rank well. But I wouldn't do it often, and certainly not with a site I wanted to grow long term.

As with so many things in SEO, it's all about risk. The more the template that you select is being used elsewhere, the more likely it might be to resemble sites that are being used for spam. I don't frankly think that this is a huge risk, but the risk is variable.

For example, if you choose a site that was templated specificially for, say, Web widgets, and 17 Web widget resellers grabbed it already, then you're the 18th site out there trying to resell Web widgets with a site looking very much like 17 other Web widget sites, that's also likely to have the same set of Web widget keywords. Why risk that?

So, either substantially modify the template, or roll your own. My 2 cents anyway.

Buying a template isn't necessarily a bad thing for SEO. As was said earlier, I'd recommend a CSS-based template. That's how I "designed" my first site and started learning HTML/CSS. I found a free website template that I liked the general layout, and then I bought a few books to help me learn the basics of CSS.

Anyway, my 2 cents is that a template is not necessarily bad for SEO. It can be nice if you don't know how or have the time to hand-code CSS and HTML.

"...told me that they have no design skills..."

I am not saying SEO and web design go hand and hand but that comment sort of tips me off that they are not very intuative. Just a thought.

One gotcha I encountered with a Joomla template (designer shall remain nameless) was hidden links. Lots of times the designer requires a credit on the footer or something - that's fine. But this particular one had a visible "design by..." link in the footer with an additional not visible link hidden with .js and called by an external CSS file. I found it using the Firefox developer's toolbar (quirks mode > links).

Just a heads up because I've seen this a couple times since too. Most common with popular CMSs like Joomla probably.