What is the biggest difference now building a house on land you buy?

I would say the biggest difference is that building materials are much more expensive now than when we built our home on 2 1/2 acres of land. Another difference now is that solar arrays are much more affordable now than then too. So, for example, I still have a friend who lives out where we owned our land and A-Frame from 1980 to 1989 when we sold it. Now everyone out there at 4000 feet has solar arrays and back up generators but this wasn't true yet in the early 1980s when solar was still too expensive for most people out there then. So, living remote off the grid is much more practical now than then. But, the main cost now is that building materials are much more expensive now than then. However, often you can salvage wood off of buildings being torn down as long as you get building inspectors to approve this wood BEFORE you salvage it for building your home. So, often you can get wood to build for free if you salvage it yourself. However, you have to be very careful HOW you salvage it so you can then reuse it on your home you are building. In other words you take down the building to get the wood you want to build with. But, you have to be handy enough to do this without injuring yourself or members of your family too. You will need specific tools like Crow bars and monkey paws for removing nails with enough leverage to do this more effective and screwdrivers to drive into the wood a little to remove the nails easier with monkey paws and crowbars.

When we bought our land in 1980 we also bought a huge clawfoot antique bathtub big enough for all our kids to get into at once when they were 5,6 and 8 years old then. We also bought an antique wood cooking stove so we could bake our own bread and cakes. My father built me from an old water pressure tank a wood stove to keep the A-Frame warm too. So, he did a lot of welding to create a wood stove for us. So, we had two wood burning stoves one a cook stove and  one a baking cooking stove that both kept our home warm some times in the winters.