The Offer Price Calculator turns a handful of inputs into three offer scenarios, a target negotiation range and a walk-away price. This page documents every step, every default and every limitation, so you can judge the result rather than take it on trust. It describes methodology v2.0.0.
The Formula
- Value basis: your comparable value if you entered one, otherwise a similarity-weighted value from the individual comparable sales you entered, otherwise the asking price.
- As-is value = value basis − condition adjustment. The condition adjustment is your repair estimate plus contingency, multiplied by the share of it the value basis doesn't already reflect: 0% if the comps needed similar work, 100% if they were in better condition, and the "unsure" share below if you don't know.
- Conservative = as-is value × (1 − starting discount).
- Competitive = as-is value × (1 + ceiling premium).
- Balanced = the midpoint of Conservative and Competitive.
- Your strategy picks which scenario is the starting offer. The target range runs from that starting offer to halfway toward your walk-away price, which is the competitive ceiling or your maximum comfortable price, whichever is lower.
Default Assumptions
These are Reaixo's general starting points, not local market data or the result of a market study. Every value is editable in the calculator's Advanced mode.
| Competition level | Starting discount below as-is value | Ceiling premium above as-is value | Capped at asking? |
|---|---|---|---|
| Low competition | 5% | 0% | Yes |
| Normal competition | 3% | 1% | Yes |
| High competition | 1% | 3% | No |
| Multiple offers known | 0% | 5% | No |
| Listing signal | Adjustment to buyer leverage |
|---|---|
| <7 days on market | -1% |
| 8-30 days on market | None |
| 31-90 days on market | +1% |
| 90+ days on market | +2% |
| Price already reduced | +1% |
| Withdrawn and relisted | +0.5% |
Buyer leverage is added to the starting discount and subtracted from the ceiling premium. A negative value (a brand-new listing) works the other way. The starting discount never exceeds 10%, however many signals stack up. If you are unsure whether the comps reflect the home's condition, 50% of the repair exposure is deducted. Scenario prices are rounded to the nearest $1,000 to avoid false precision.
Input-Quality Score
Every result carries a 0–100 input-quality score. It measures how complete and well-supported your inputs are, not how accurate the result is or how likely the offer is to succeed. It is the share of available points earned:
| Factor | Max points | What earns them |
|---|---|---|
| Value evidence | 35 | Several qualified comparable sales you entered score highest. A single comparable value scores 20. Asking price only scores 5. |
| Evidence freshness | 10 | How recent your newest dated comparable sale is. |
| Repair estimate | 20 | Who produced the repair figure. "Unsure" scores 0. |
| Condition basis | 10 | Whether you know if the comps reflect this home's condition. |
| Listing signals | 10 | Whether days on market is known. |
70 or above is High, 45–69 is Moderate and below 45 is Low.
Financing, Cash and Appraisal Risk
For every scenario the calculator estimates monthly housing cost (principal and interest from a standard amortization formula, plus your tax, insurance and HOA inputs; mortgage insurance is not included), cash to close (down payment plus your closing-cost percentage, less any seller credit you request) and a possible appraisal shortfall. The shortfall assumes an appraisal near the as-is value. That matters because lenders generally size the loan on the lower of the purchase price or the appraised value. Fannie Mae's Selling Guide, for example, calculates the loan-to-value ratio on a purchase using the lower of the sales price or the appraised value.1 The U.S. Consumer Financial Protection Bureau notes that buying a home for more than its appraised value is risky and that a low appraisal can be used to renegotiate the price.2
Appraisal exposure is banded by the gap as a share of your offer: up to 2% is low, up to 5% moderate, above that high. It is not a probability that the appraisal will come in low.
Limitations
- The calculator uses only the numbers you enter. It does not look up the property, its sales history or local market data.
- Default percentages are general assumptions, not local market evidence. Local norms vary widely.
- It does not predict whether a seller will accept an offer, and it does not replace an appraisal, an inspection, or advice from your agent, lender or attorney.
- Repair presets are rough illustrations, not estimates for any specific home.
- Financing figures are estimates. Your lender's Loan Estimate is the authoritative source for your costs.
Sources
- Fannie Mae, Selling Guide B2-1.2-01, Loan-to-Value (LTV) Ratios. Accessed October 10, 2026.
- Consumer Financial Protection Bureau, My appraisal is less than the sale price. What does that mean for me? Accessed October 10, 2026.
Version History
v2.0.0: current version, documented on this page (published October 10, 2026). Saved analyses record the version they were calculated with and are recalculated, with a notice, when reopened under a newer one.
Related terms: Appraisal Gap, Comparable Sales in the full glossary.