Real estate agent · Saint Louis Mo Metro

Sell smarter with Katherine Effinger.

Katherine partners with Zoom Casa so you can see exactly what your home would net — cash offer, repairs covered, the works — before you list, and before anyone asks for your contact info.

Start here · No email required

See your offer first.

No email needed yet — see what you'd net first. Katherine stays your point of contact start to finish.

Katherine Effinger
About Katherine

A real person, on your side.

Katherine Effinger serves buyers, sellers, and investors throughout Jefferson County, St. Louis County, St. Charles County, and across Missouri—especially clients who need clear guidance, hands‑on support, and a Realtor® who can step in when time, cash, or resources are limited. As a second‑generation agent with deep local roots and strong business expertise, she helps clients overcome obstacles like cleaning, staging, and unfinished projects so they can move forward confidently. Her client‑first approach makes her a trusted, full‑service partner for anyone working toward their real estate goals. Office 636-937-7727 or cell 314-221-5792

What Katherine can put to work

Three programs. One recommendation.

Katherine stays your agent of record. Zoom Casa is the underwriter and operational backstop behind the offer — never the salesperson.

Up to 85% up front, less reserves. The remaining balance (minus a one-time program fee) is paid when the home resells on the open market. Final terms are issued in writing — not all properties qualify.

The standard

One standard. Six rules. Every consultant.

Whichever consultant you talk to, these are the things they will not bend on. They are the operating creed John writes for the floor — Casa Core. Now you get to hold us to them.

  1. 01
    Your offer is back in 24 hours.
    Underwritten by hand by your consultant before they call. No "we strive to," no "times may vary." Twenty-four hours.
  2. 02
    If the math doesn't work, we tell you.
    Same call. We'd rather lose a deal cleanly than win one with pressure. If a different option fits better — listing traditionally, a HELOC, sitting tight — we say so.
  3. 03
    You get one named human, start to close.
    Direct line, direct email. The same consultant from offer to keys. Not a rep, not a queue, not a "your account is being transferred to."
  4. 04
    Every fee is on the term sheet.
    Program fee, holdback, closing math, the upside split — all on one page, all in plain numbers. No "subject to underwriting," no surprises at signing.
  5. 05
    You keep the upside. We document the floor.
    Cash Offer+ pays you up to 85% upfront in as fast as 10–15 days; the remaining 15%+ (minus fee) comes back when the home re-sells. We earn on the program fee, not on your equity.
  6. 06
    No pressure language. Anywhere.
    No countdown timers. No "act fast." No "limited spots." If the deal works for both sides, both sides will know within an hour of the call.

Start with Katherine.

Put your address in the box above and you’ll have an underwritten offer back within 24 hours — reviewed with Katherine Effinger of Main Key Realty LLC. If your math already works, the call is short. If it doesn’t, you’ll hear that on the same call.