VCAT likely outcomes?

Hi
This question is inderictly about our investment property….

Were about to commence an action through VCAT
Bathroom tiling disaster which the tiling layer mucked up our bathroom through poor workmanship (permanently stained tiles between leaving grout on too long and using hydrochloric acid to remove grout residue).
The tile layer is blaming the tiles. We, other tilers, the tile retailer and supplier all believe it is absolutely the tile layers fault, and that there is no fault with the quality of tile.

VCAT nutshell questions.
– Does the VCAT process become costly, or can I assume one may represent themselves without the need for costly legal bills…
– If there are legal costs, could / would VCAT stipulate that the losing party pay the others legal costs.
– Do VCAT decisions rest as final or can the loser, take issue to a higher court….
– Is the VCAT process drawn out and costly.
– If as we expect to win, would the VCAT decision if in our favour hold weight with the requirement of the tradesman to pay our costs for repair or could he ignore it, and force us to take it to a higher court.
– Any referrals to experts in this area that could provide some basic free legal advice in reference to the above would be great!!