Good point Scott, I never really considered that when I posting my reasoning.
I've had the chance to give it some thought (remarkable, huh?) and as much as I'd like to provide a line-by-line cost analysis of a project build, truth is, I don't know if I honestly could, or if I did, what would the reader gain from it?
What I mean is...my spares box gets a workout with every project, I do a lot of scratchbuilding, and I turn and mill and cast many of my own parts. Are those options available, or even useful, to the average modeler?
I honestly can't think of the last time I bought a kit and a detail set, and just built it. If that were my norm, it'd be easy to say I spent $30 on the kit and $18 on the detail set. I don't know how many of us actually build this way, but I'd tend to think most of us are somewhere in between those two levels.
Of course, it could get ridiculous too...
I spent $30 on the kit, $50 on resin bits, $25 on PE, $40 on Frui tracks, $7 on decals, then I spent $600 on a lathe to turn the barrel and $300 on a compressor to run the $400 Iwata airbrush I bought for this project.
I think that most "super" models that we see start out with a basic kit (obviously, scratchbuilt models are the exception). I think the average reader has the ability to read a story, understand that the builder started with a $30 tank kit, and added lots and lots of details to it. If he (the reader) is at the level of the builder, then chances are he already knows how much it'll cost to get that level of detail.
Most readers will look at a model and say, "I'm not going to add ________ because..." It could be money, skills, experience, or desire (or lack thereof). Usually, readers will say something to the effect that "I'm not going to scratchbuild a replacement mantlet just because the bolt pattern is wrong, but I am going to add a replacement barrel like he did."
Eventually, with each project, the reader's skills and confidence will increase, and eventually (it could take years) he finds himself adding tons of details to a project. That's the typical progression of a modeler. Eventually, we find that we're not newbies anymore. Most of the time, we don't know when we stopped being newbies and started becoming "experienced" modelers.
I guess it boil down to common sense, too. If you read a story and the builder says he added this resin set and that PE set, it's pretty likely that it's going to be expensive if you try to replicate the project.
Maybe I'm an exception to the rule...but I can't tell you where my kits came from, how long I've had most of them, or how much they cost me. I'm constantly swapping and trading kits and buying collections. Same with my detail parts, I have no clue what I have. Sometimes, I'll open a box and find it jam-packed with aftermarket details, and I have no clue where they came from, or where I got them! It's hard to quantify something like that.
I'm babbling again...
Jeff