My budgeting mind is in the past, where if you bought a lot of various different parts, you took the budget hit for all of them, then got some recoup by selling off the ones you didn't use. The impression I get with the new budgeting rules is there is some more "flexibility".
A part’s cost may be pro-rated by weight or quantity if from a homogeneous parts lot (example: zip ties, nuts and bolts, a box of 20 identical axle shafts, etc.), or relative retail value if it was purchased as part of a heterogeneous parts lot (all-you-can-carry sales, storage unit buyouts, garage cleanouts, etc.) Relative retail value is calculated as follows:
Assign and prove a fair market value to every part in the lot.
Add those fair market values together to calculate the total fair market value of the lot.
Express the fair market value of the part you are pro-rating as a percentage of the lot’s total fair market value.
Multiply the actual price paid for the lot by that percentage in order to determine the part’s relative retail value.
My examples are buying from an individual off FBM, the GRM forums, CL, etc.
Firstly, let's say for example, someone is selling a bunch of different parts: Part A($50), Part B($100), Part C ($250). If I ask them if they'd take a lower price if I bought all three, say $350, but only used Part A and Part C on my challenge car. I kept Part B around for one of my other projects. If I am interpreting the rules correctly, does that mean, Part A gets budgeted at $43.75 ($50 * ($350/$400)) and Part C gets budgeted at $218.75 ($250 * ($350/$400))? Would this mean my overall and recoup budget is not affected by the existence of Part B?
Second question, does the quoted rule above work when buying a parts bundle from an individual, that they already had advertised as all the parts together? Say I buy 10 heterogeneous items in a lot for $1000, I could assign FMV to each of them(that all together exceeds $1000), come to the forum for approval, then price each item based on FMV * ($1000 / Sum(all 10 FMVs))?
I want to be 100% sure I have this right as it could affect the direction of my build significantly. Seems like it could really make it more important to buy parts in lots versus individually, if the total cost of the lot doesn't hit the budget and require some recouping.