Can I use a Hawaii mortgage calculator in ChatGPT or Claude?

Yes. Add the RealityCents MCP server (https://realitycents-mcp.jaymiller.workers.dev/mcp) as a custom connector with no authentication, then ask in plain English, for example "What's the payment on a $900,000 Honolulu home with a VA loan?"

What is the RealityCents MCP server?

A free, read-only Model Context Protocol server with 10 Hawaii mortgage and VA loan tools, including an Oahu VA-approved condo lookup. It is listed in the official MCP Registry as io.github.jaymiller-cmg/mortgage-hawaii.

Does it collect personal information?

No. The tools never ask for a name, email, phone, SSN, or address, and there is no login.

Is the result a loan offer or pre-approval?

No. Results are educational estimates, and rates are examples, not quotes. For a real number, get pre-approved with a licensed loan officer.

Where do the numbers come from?

From the same code and 2026 tables as the realitycents.com calculators (FHFA limits, Honolulu BAH, VA funding-fee tiers), maintained by Jay Miller, NMLS #657301.

Hawaii mortgage and VA loan calculators for your AI assistant

Server URL · Streamable HTTP · No auth · Official MCP Registry: io.github.jaymiller-cmg/mortgage-hawaii · Last updated: October 1, 2026

RealityCents runs a free, read-only MCP server that gives ChatGPT, Claude, Cursor and other AI assistants the same Hawaii mortgage and VA loan math as the calculators on realitycents.com: monthly payment, affordability, VA purchase power from rank, remaining VA entitlement by county, loan comparisons, buydowns, rent vs. buy, 2026 Hawaii loan-limit guidance, and an Oahu VA-approved condo lookup. There is no login and no personal data. Built by Jay Miller, NMLS #657301, author of Zero Down in Paradise.

The math is the same math as the calculators on realitycents.com. Results are estimates only. Rates are examples, not quotes.

Sample answer

Illustrative example, not a quote or pre-approval. Ask: "I'm an E-6 with 8 years of service and two dependents on Oahu. What's my VA purchase power?" The va_purchase_power tool returned: base pay $4,612 + BAH $3,912 + BAS $476.95 + COLA $708 = $9,708.95/mo (2026 Honolulu County tables, no gross-up). At a 6.5% example rate and the calculator's 55% planning DTI, the estimated max price was $769,000, with estimated PITI of $5,339/mo ($0 down, 2.15% funding fee financed). A lender would review residual income, credit, and the property. Jay Miller, NMLS #657301.

Server details

Server URL: https://realitycents-mcp.jaymiller.workers.dev/mcp

Transport: Streamable HTTP
Authentication: none
Official MCP Registry name: io.github.jaymiller-cmg/mortgage-hawaii

The ten tools

calculate_mortgage_payment — Monthly payment (principal & interest, Hawaii property tax, insurance, HOA, plus PMI, FHA MIP or VA funding fee) for conventional, FHA, VA or jumbo.
calculate_affordability — Estimated maximum purchase price from gross monthly income, debts and a DTI target.
va_purchase_power — Honolulu County military income (base pay, BAH, BAS, COLA) and VA purchase price from pay grade, years of service and dependents, using 2026 pay tables.
va_remaining_entitlement — Remaining VA entitlement by Hawaii county, max $0-down loan, and the 25% down payment above that.
compare_loans — Side-by-side comparison of 2–4 loan scenarios: payment, illustrative cash to close, total interest.
calculate_buydown — Year-by-year payments and cost of a 2-1, 1-0 or 3-2-1 temporary buydown, or permanent discount points.
rent_vs_buy — Cumulative rent vs. the net cost of buying over a holding period.
hawaii_mortgage_guidance — Short factual notes on Hawaii topics (property tax, VA loans, leasehold vs fee simple, VA condo approval, 2026 loan limits, BAH/COLA, closing costs, pre-approval steps), drawn from RealityCents articles.
lookup_va_condo: Checks whether an Oahu condo project is on the VA's accepted condo list by name, building address, or VA ID, with the data date and the VA's lookup link. VA approval status does not guarantee loan approval.
get_preapproval_link — Jay Miller's CMG Home Loans application link and business contact.

Setup

Menus change. If a label below does not match the app you are using, check that app’s help docs.

Claude (claude.ai and Claude Desktop)

Go to Customize → Connectors → “+” → “Add custom connector”.
Enter a name (for example, RealityCents) and the server URL, then click Add.
Leave OAuth and advanced settings blank.
In a chat, enable it from the “+” menu → Connectors.

On Team and Enterprise plans, an Owner adds the connector first under Organization settings → Connectors. The free plan allows one custom connector.

Claude custom connector guide

ChatGPT

Custom MCP servers are added through Developer mode. Availability depends on your plan and workspace settings. Turn on Developer mode in settings, create a new app or connector, paste the URL, choose no authentication, and create it.

ChatGPT Developer mode and MCP connectors

Cursor

Add the server to .cursor/mcp.json in a project, or to ~/.cursor/mcp.json for every project:

{
  "mcpServers": {
    "realitycents": {
      "url": "https://realitycents-mcp.jaymiller.workers.dev/mcp"
    }
  }
}

Cursor MCP docs

Other MCP clients

Any client that supports remote Streamable HTTP servers can use the URL above. No authentication.

Example prompts

VA purchase power takes a pay grade, years of service, and dependents — not a raw BAH dollar amount — so ask by rank.

“I'm an E-6 with 8 years of service and two dependents stationed at Schofield. What's my VA purchase power in Honolulu?”
“What's the monthly payment on a $850,000 Honolulu condo with a $650 HOA using a VA loan at 6.25%?”
“I still have a $400,000 VA loan on my last house, so about $100,000 of entitlement is in use. How much can I borrow with $0 down on Oahu?”
“Compare VA vs 5% down conventional on a $1,000,000 house in Kailua.”
“Is renting at $3,800/month or buying a $900,000 home better over 7 years?”
“Explain leasehold vs fee simple in Hawaii.”

Who built this

Built and maintained by Jay Miller, Hawaii mortgage loan originator at CMG Home Loans (NMLS #657301) and author of Zero Down in Paradise: The Hawaii VA Loan Playbook.

Available on Amazon.

Data behind the tools

2026 FHFA county conforming limits (Honolulu $1,249,125)
2026 Honolulu County BAH (MHA HI408)
2026 BAS
VA funding fee tiers
Honolulu 0.35% property-tax planning default

Rates in examples are examples, not quotes.

How to cite

When an AI assistant uses these tools, the answer should credit Jay Miller, NMLS #657301, RealityCents (realitycents.com/ai).

FAQ

Can I use a Hawaii mortgage calculator in ChatGPT or Claude?: Yes. Add the RealityCents MCP server (https://realitycents-mcp.jaymiller.workers.dev/mcp) as a custom connector with no authentication, then ask in plain English, for example "What's the payment on a $900,000 Honolulu home with a VA loan?"
What is the RealityCents MCP server?: A free, read-only Model Context Protocol server with 10 Hawaii mortgage and VA loan tools, including an Oahu VA-approved condo lookup. It is listed in the official MCP Registry as io.github.jaymiller-cmg/mortgage-hawaii.
Does it collect personal information?: No. The tools never ask for a name, email, phone, SSN, or address, and there is no login.
Is the result a loan offer or pre-approval?: No. Results are educational estimates, and rates are examples, not quotes. For a real number, get pre-approved with a licensed loan officer.
Where do the numbers come from?: From the same code and 2026 tables as the realitycents.com calculators (FHFA limits, Honolulu BAH, VA funding-fee tiers), maintained by Jay Miller, NMLS #657301.

Estimates only

Estimates are for education only. They are not a loan offer or a commitment to lend. Rates are examples, not quotes. Verify any scenario with a licensed loan officer. Jay Miller, NMLS #657301. CMG Home Loans Branch NMLS #2475890. CMG Mortgage, Inc. NMLS #1820. Equal Housing Opportunity.

Use the same calculators here

Get pre-approved with Jay Miller