Hi and Sorry in advance.

I think I know the answer, but I just want to be 100% certain

We have a PHP created webpage with an on-going Cost and an Available Options dropdown box. Each Available Option has a cost associated with it. The Cost is temporarily held in a MySQL database until the checkout phase.
My Boss wants the display of the Cost to be updated when the Available Options box value has been changed, all this without the webpage being refreshed in the browser, i.e. just the Cost value is updated from the MySQL database with the additional Available Option cost.

I am assuming that the only way is the AJAX route, is this correct, or is there a better solution?

Thanks and huge appologies again,