Something like the image below (pulled off of google...obviously the keys would be more modern keys).

Here in southern California on the new houses, rather than the tropical landscaping that's prevalent I'm thinking we should do a more modern xeriscaping. 

It's huge and the amount of power you get out of it  isn't even close to what you need to power a modern home.

Popcorn ceilings  must go. knockdown walls looks good if done properly and hides flaws. orange peel walls is disgusting and lazy. santa fe finish on walls and ceilings  is modern and a nice meet in the middle between smooth and knockdown. smooth walls pays for itself.

Modern environmental regulations either discourage or ban the use of cesspools, and instead connections to municipal sewage systems or septic tanks are encouraged or required.

But most modern furnaces have electronic ignition, so there is no pilot light to burn.

They are considered a modern classic so it can actually appreciate in value as you own it.  

That is a modern bs thing made up by local government to victimize ordinary people.If a parent is a criminal for wanting a better education for their child then the teachers and schools are equally criminal in providing a bad education, which they are paid handsomely for by the taxpayer.Sign of the times when parents are criminalized for wanting the best for their children.

If they were installed well and were a bit more modern we would probably be keeping them, but as it is they are an eyesore to the tenants, very difficult to get clean at turnover, and are not sealed up very well.

If it was built in the 30's and it is not built to modern codes there may not be much cost savings for you.