Trinity Falls carries a McKinney address and pays no McKinney city taxes — because it sits in the city’s extraterritorial jurisdiction, served instead by McKinney MUD 1 (~$0.9875) or MUD 2 ($1.05 since 2019). That single structural fact reorganizes the entire budget: the MUD is roughly 40% of the bill, it ignores the $200K senior shield and the freeze completely, and no incentive package changes it. Everything else on this page is detail.
| Item | Figure | The Footnote That Matters |
|---|---|---|
| MUD levy (rep. $475K home) | ~$4,700–$5,000/yr | MUD 1 ~$0.9875 (≈ $0.46 water/sewer + $0.35 road + $0.18 ops, trending down from $1.019); MUD 2 flat at $1.05 since 2019. Which MUD serves the lot changes the bill — confirm on the entity list |
| City line | $0 | The offset everyone forgets: McKinney’s ~$0.42 city rate is NOT levied here. The honest comparison is MUD-versus-city (~$0.99 vs ~$0.42), not MUD-versus-nothing |
| School + county (over-65 filed) | ~$3,400–$3,900/yr after exemptions | McKinney ISD line shrinks under the $200K shield and then freezes — the toolkit works normally on this half |
| HOA | Dual structure — Del Webb sub-association + Trinity Falls master | Get both schedules itemized in writing; single-number quotes here are how budgets go wrong |
| Builder incentives | ~$13K options + $20K flex cash (through mid-2026) | Real money — and worth ~6–7 years of the MUD premium over a city address. Negotiate them, then stop letting them anchor the math |
| Insurance | ~$2,600–$3,400/yr typical | New-build roofs price well today; the hail deductible structure is still the line to read |
Stack a representative over-65 couple in a $475K build: school-and-county after exemptions ~$300/mo and freezing, MUD ~$400/mo and floating, dual HOA call it ~$250/mo pending the itemized schedules, insurance ~$250 — roughly $1,200 a month of carry, of which the largest single line is the one no Texas senior protection touches. Across ten years that MUD line alone runs $50,000–$58,000 under ordinary appraisal drift, and the decade total lands near $135,000–$145,000 — meaningfully above the Robson/Frisco Lakes band at a similar house price, with the gap explained almost entirely by the district. The MUD 1 trend line (rates stepping down as bonds amortize) is the legitimate counterargument: district rates do fall over decades, and a buyer holding twenty years will likely watch it happen. A buyer holding seven should price the rate as-is.
Full structural story: the Trinity Falls guide · why this matters more after 65: the Over-65 Guide · Collin County guide
The lot’s entity list, both association schedules itemized, and the decade table with the MUD line shown honestly. Before the design center, not after.