Trying to avoid too many page templates

I’m converting an HTML site with about 100 pages to a WordPress site. For now, the site will have only pages and not posts. I’ve successfully developed a custom theme and I’m reading up on the page templates – creating them and their use.

I’m not able to get my head around how to avoid having to create a page template for each HTML web page. For example, the HTML site has a header area, but nearly every header has a unique photograph in it. So for example, the HTML looks like this for 2 different pages:

<!–<header with one photo –>
<div class=”jumbotron photo1“>

<!–<header with a different photo –>
<!–<div class=”jumbotron photo2“>–>

Or take the page footer. Currently each page loads some unique JavaScript code just before the closing body tag.

The only way I can think of handling uniqueness like these examples is by creating different page templates.

That would seem to defeat one of the major advantages of using WordPress however.

What’s the best practice here?

Thank you.