The background is a site which features holiday properties, and we are at the point where we would like to add a ratings system allowing people to vote.

There is currently a back end database built for this.

In which case I'd be really grateful for any pointers as to how difficult / complicated it might get.

Off the top of my head, I'm thinking along the lines of....

We already have a table - Lodges. So in theory this just needs two new fields, 'Average Score' and 'Total Score'.

And we need a new table 'Lodge_Scores', with a one (Lodge) to many (Scores) relationship.

Which seems straightforward enough.

The bit I'd be less sure about would be how to calculate the average score and total score, and get those values into the 'Average Score' and 'Total Score' fields.

Hopefully that makes sense, and might not actually be too complicated.