A 2-1 buydown temporarily lowers your mortgage payment for the first two years of the loan — for example, a 6.5% rate could effectively act like 4.5% in year one and 5.5% in year two, before settling at the actual 6.5% note rate from year three on.
The note rate itself never changes; funds are simply set aside upfront to subsidize part of the payment during that window. Depending on the loan program, a seller may be able to contribute toward the cost — which is one more reason purchase price isn't the only thing worth negotiating on an offer.
This isn't the right fit for every buyer — you should be comfortable with the full payment once the subsidy ends, and loan programs and seller-contribution limits vary. If you're thinking about buying in Orange County and want to understand the ways an offer can be structured, reach out.