Hi Darrell,

I built a website for a couple's upcoming wedding and it's been great.

For an RSVP form, you should investigate the build-in form block. The form block can be set up with different questions and configured to email the responses somewhere. It will also record the responses (which can be viewed/exported from the dashboard).

If that doesn't have what you need, you should simply investigate some of the more advanced forms you can get from the marketplace. Don't think of it as RSVP, just think of it as a fancy contact form I reckon.

As a side note, one thing I've noticed about the website we've built is that it's been viewed by more people on mobiles than on desktops. I think it's just one of those kind of sites where it comes up at get-togethers and people whip out their phones. So I'd suggest that if you are building or selecting a theme for this site, to aim to make it mobile responsive.