Typewriter Value Checker is a deterministic resale worksheet. It combines model priors, condition adjustments, confidence rules, and fee-aware sale channels to produce an estimate for pricing decisions, not a certified appraisal.
The worksheet begins with in-code ranges for common Royal, Underwood, Smith-Corona, Remington, Olivetti, Hermes, Olympia, Corona, Woodstock, and IBM families. Unknown models fall back to brand, era, and style priors instead of forcing false precision.
Working state, carriage movement, cosmetic grade, mechanical feel, case, manuals, original spools, restoration status, and shipping preference move the range up or down. Missing details widen the output rather than pretending the machine has been inspected.
Local sale, online marketplace, dealer offer, and quick-lot outcomes use different fee, packing, damage-risk, discount, and speed assumptions. The highest gross asking range is not always the best net result.
A narrow range requires evidence. When model, era, working state, case, or selling channel details are weak, the calculator lowers confidence and explains what would make the estimate stronger.
High confidence
Brand, model family, condition, working state, case, and channel details are specific enough to keep the range tight.
Medium confidence
The machine is identifiable, but one or two important proof points are missing or condition details conflict.
Low confidence
Brand/model is vague, mechanics are untested, the item may be rare or heavily altered, or available comps are weak.