If your house is strata title, the installation cost will be higher, because management office don't allow to install anything on exterior wall surface. Like mine, the DB is at downstairs storeroom, so the cable have to be pulled from roof top to the rear exterior wall and then all the way go into the kitchen ceiling, and continue pull to my DB. So from rooftop to kitchen's exterior wall, I have to ask my own contractor to hack and conceal the cable and repaint the wall surface, it will cost me about 1k, the solar company can do that but usually will cost more. Minor hacking inside the house, solar installer can cover, but I need to do plaster ceiling to cover it, but anyway I will still do plaster ceiling for whole house so this is not counted.
So if there is no restriction on your exterior wall, you don't need to pay anything. They will put cable in pvc pipe stick on your wall surface.

If your house got sub DB on topper floor, then it will be easier, they can just pull the cable under roof tile go into your house connect to sub DB on upper floor, of course you need to pay if you wan conceal the cable inside your house.

Another thing is the 10mm cable from DB to car porch for EV charger. I haven't received quotation for this.

So it would be great if Sime Darby can conceal all cable inside wall for you with ready points, the solar installer can just come to install, save alot of effort, maybe can save 1 to 1.5k for conceal cost. Just not sure if the solar company can give further discount for hacking and cable cost, since it is included in package