The manufacturer's own sales rep can be the most honest voice in a prefab pro forma
Consider a small operator planning to drop three prefab units on three lots he already controls in a first ring suburb, and an investor sitting in on the manufacturer's sales call to hear how the delivered price gets built. The rep walks through the box. Unit price lands right around the number everyone quotes, low six figures, and it covers the shell, fixtures, and appliances. The operator asks what the total installed number looks like in that county, and a rep worth trusting will go quiet for a second and then say the delivered price is honest but customers still average 60 to 90 percent on top of it once site work, foundation, utility trenching, crane day, and permits are added, worse on sloped lots. A rep who tells a buyer to walk away from his own product if the pro forma assumes an all in number below that range is telling the truth about the part he doesn't sell. A model built at $145k per unit against a real number closer to $210k is the gap that kills these deals. Rents around $1,500 in that submarket work fine at $145k all in and do something very different at $210k. That's the arithmetic worth running before committing to any prefab pro forma: get the installed number from someone with no stake in underselling it, not just the unit price.