Decking over Concrete

We have an Alfresco area in our new house. Due to an issue with the surface at handover (mortar has been left on the floor), the builder has offered us an epoxy be layed.
Our aim was to always maybe deck the area. We had considered asking the builders to put the money of an epoxy layer into the cost of decking the area.

My question is, if I am to get a deck putdown on concrete, is there some sort of anti mold put on the concrete?
My concern is as time goes on, if food or drink (3 young kids) is spilt, will it begin to smell as it would not dry quickly due to it being undercover?

Not sure if my concerns are unrealistic

Eventually dirt etc will get in there and accumulate which will hold moister etc, results: rotted timber/dry rot, fungi growth

You have to maintain the ability for water to escape and dry out

I assume that you only have a max of 100mm difference in height internal to external

The builder is offering the best possible solution, it is his legal responsibility to rectify which sounds like he is willing to do

If you want a timber look, negotiate with the builder for a composite material faux timber deck such as
https://www.ekologix.com.au/

Welcome to the forum.

I built my 80-90sqm deck over concrete that I poured beforehand, precisely to avoid soil sitting damp beneath the deck and to stop weeds etc from growing up through it. I had a minimum of 100mm beneath the bottom of the boards and this allower me to leave a 10-40mm gap under the bearers/joists to allow for drainage and airflow. I used 35x120mm decking boards and left a good 7-8mm between boards for expansion and airflow. It's been 2 years and haven't had any issues. No smells, or damp etc.

Cheers, Dom