If you have a drill,
they're stupid easy to make. Read about what size holes the bees in your area like. And leave a smooth edge on the entry! They won't use it if they sense a risk to their wings.
Might as well roll your own, not like you can reuse them after they nest. Mites and such are an issue.
You can reuse them, but you have to carefully clean the nesting holes. I have professionally made bee houses that I use. The wooden blocks that hold the nesting holes can be removed, opened, and sanitized. This also allows you to harvest cocoons to keep safe from predators/weather for the next year.
Yay! Me too! I had so many different species visit my yard this year. Like 3 different species of big 'bumble bees'. And so many of the other kind. I like the iridescent green one!! :-D