If a company can't show you a running version of any app not only that they've developed (and still support) but also that they're developing, don't work there. Heard of daily builds? You need them. You need that overhead in place already to ensure that you've got a mature, robust development process in place.

And if you find yourself someplace that doesn't happen now, start it. It's a lot of overhead, sure, but it's really a requirement for a workplace that's not going to stick you with horrible to handle "legacy" work (eg, "Coder X left the company and the project's yours now." Without the symptoms of a mature coding process evident, you could end up with the dreaded worst case here -- code that Coder X could upgrade in an hour but that'll take you three weeks just to begin to understand. Why does this happen? Coders without processes tend to create cyborgs, not maintainable code. This is due to a number of reasons: laziness, perceived job security (I'm the only one that can do this), lack of skill, etc.)

At any rate, you've been warned.