sdr can probably help you more with the santa fe hills question.
There is a Santa Fe Hills in San Marcos and I am 99.9% sure that is NOT what you are looking for and there is a Santa Fe Hills subdivision in 92075, Solana Beach which is more desireable then San Marcos but still don’t think it fits your bill. I do not really know what map you are looking at with regards to the RSF district. I went into the MLS and typed in Santa Fe Hills in the subdivision field to find out the locations.
Have you thought about the Del Mar Mesa? That is on top of the Mesa to the south of Highway 56. Ask your agent to show you some properties over there. Not sure if you will find a full acre lot but it may be more to your liking.
