I apologize if I’m telling you something that you already know, but wood choice is important for raised beds. Don’t get pressure treated because the chemicals leach into the ground. And other woods will rot from the moisture.
My wife probably wouldn’t know to look at the lumber before putting it on the cart.
I’ve wondered about using Hardie board but never looked into it. EDIT - quick search says that it is not good because of prolonged contact with moisture.
Depending on your dirt (if it is heavt clay for instance) some fruit trees like peaches and cherries prefer a slightly raised bed. One board instead of 3. It keeps their feet from standing in water. Apples will be OK.
Don’t be stingy on fertilizer for either the trees or vegetables. Not spraying fruits is a fine idea. But if you actually want fruit you will need to spray. Grapes are pretty steady. My blueberries always kick ass. Peaches have been kicking my ass.
University extension services are great sources for what you are doing. Off the top of my head Purdue, Washington and I think Minnesota have good web sites.
Potatoes and onions are cheap at the store and decent quality so I don’t plant those. Tomatoes, cucumbers, peppers are all much better and tend to do well.
Raised beds take more water. Kind of a trade off.
The best critter deterrent is an electric fence. Plug in units are cheap
SHAME, I mocked my wife for wanting to grow potatoes for the same reason, turns out, they are the best thing out of the garden. Proper new potatoes fresh from the dirt are easily the best thing you can grow.
I have heavy clay soil. I can get around it a lot with other things with a lot of composting and fertilizer, but it is hell on growing potatoes. After a few years maxing out with golf ball sized potatoes I gave up.
We are too sandy, great for taters, rough on everything else. Lots of grass clippings and leaves and starting to turn things around, but still too much sand.
Potatoe plants are also quite pretty. I grow a few varieties every year. Always end up with more than I can eat. Just save the rest as seed potatoes and replant the following year.
If you have rabbits in your area a few feet of chicken wire around the bed will prevent them from eating your stuff. I planted some hazelnuts. I live in town. I cannot shoot the squirrels or effectively fence them out. The squirrels clean me out every fall.