I'm glad everyone is okay. I thought the latest advice was to shelter next to a large solid piece of furniture (a bed counts) rather than under one. The survivors of building collapses have been found in the void formed next to large furniture. I'm not sure how much that applies to wood frame one story houses as opposed to high rises. I was awakened by the Oakland 4.3 quake last July - many stories up in a hotel room. I rolled off the bed and crouched next to it - then wondered if it really was a quake vs a bad dream but the next morning the news confirmed it.

Figuring out the square footage of the home is just one step in properly sizing a system. Remember insulation, windows, etc. I recommend a full load calculation on the house.

The first thing you need to do is reconfigure that walkway. The landing at the base of the steps is skimpy and awkward, demanding an immediate left turn. And the walkway itself is far too narrow. Should be at least 4' wide....5' is even better. Once a proper walkway is defined and sited, you can/should increase the width of the planting beds, especially on the walkway side, to accomodate better plantings. Anything you do now afa the plantings are concerned will have to be redone or possibly replaced once the walkway is restructured so save your time, effort and $$ and address that before you do anything else. Moving, adding or replacing shrubs/trees now is just applying a bandaid to a poor design situation.

Charming house, and I'd want to keep the character. After much research, my daughter ended up with Anderson 400 Woodwright double hung windows for her 1950's house. She did 6 over 6 instead of 8 over 8 because her openings were a bit narrower than usual. We also looked at Marvin Integrity, but Anderson had a few features we liked better and were a bit better looking to us. They are wood on the inside but clad on the outside for no maintenance. It's a nice looking product. Of course, if wanting all wood, then Marvin makes a nice one. None of these are inexpensive.