As of today, any new home built in 2020 and later, must  use solar power. The new mandate followed a (unanimous) vote by the Building Standards Commission.

 

Kent Sasaki, a structural engineer and building standards commissioner said, “These provisions really are historic and will be a beacon of light for the rest of the country. (It’s) the beginning of substantial improvement in how we produce energy and reduce the consumption of fossil fuels.”

Although, there was little opposition to the vote, the commission later received letters that opposed the mandate, citing its potential increase in cost to the Orange County register. According to the Miami Herald, “energy officials estimated the provisions will add $10,000 to the cost of building a single-family home — about $8,400 from adding solar and about $1,500 for making homes more energy-efficient. But those costs would be offset by lower utility bills over the 30-year lifespan of the solar panels, officials said.”
Since the mandate mostly affects homeowners, this means they have two options to eliminate the upfront costs: leasing the solar panels or signing a power purchase agreement that pays for the electricity without buying the panels.

One solar-industry representative said the net savings from adding solar power will be around $40 a month or nearly $500 a year.

There is some discussion on costs aside from actual implementation of solar power panels, for example, home-buying and selling costs and how they could be affected. The utility costs will be lowered in terms of using solar enegery as a replacement for current energy standards and some say this will not directly cause an increase in housing price.
Homebuilders and owners have long prepared to meet a Building Standards Commission proposed requirement that all new home be “net-zero,” meaning they would need to produce enough solar power that would,Solar Panels  in turn, offset all electricity and natural gas consumption over the course of a year.
Read more here: https://www.miamiherald.com/news/politics-government/national-politics/article222729945.html#storylink=cpy