The slope issue I will let others address, but you definitely want your boxes on level ground.

For the deer an 8' tall fence is reliable, shorter fences also work in many cases, but the trick is to deny the deer a safe landing spot. If the deer has no clear landing area this often dissuades them from making the leap. Also, with a 4' fence you will need to keep the plants away from the fence or the deer will just lean over and nibble at whatever is within reach.

Making the mix in the fall is a good idea. Less work in the spring when you want to get planting. Cover cropping is a great thing to do, but not absolutely necessary.

Composting right in the garden is fine when there are no plants, but be careful when there are plants. There are many insects that eat rotting food items that will also eat ripe food items on your plants. Burying the scraps in the boxes will be preferable to leaving it on the surface where it is more accessible to insects.

Have fun!

Building on a slope: I am doing it on a smaller slope where I lose about 8" over 4 feet. What I did was build a normal 8" 4x4 bed then laid it out. Then with some levels I jacked up the low end until it was level. From there I templated and cut boards to fill in the sloping sides and the bottom. It was a bit of work, but they are level.

It messes up the calculations for how much mix you will need - but carrots will probably grow great on the 3' deep side! I should get a photo of a local garden here for you - its on the side of a condo complex, but the slope has to be like 45 degrees. Its astounding.

Deer: I believe you will need at least 7 feet. But the good news is that you can use deer netting which is next to invisible. They apparently don't like the way it feels on the nose and if they can't reach over it they go away. The most obvious part are the support poles, but you can hang flags from them - if they complain about it, you can always insinuate they are not patriotic...

I agree with justaguy2 on the clear landing. I know someone with a very small fence, but its a very small area and the deer won't jump into the clutter.

Thanks for responding

I appreciate the composting tips. From what I gather sounds like at least this year I can compost in my boxes, but I will start a separate compost pile once is gets closer to spring.

That is good to know about the invisible deer netting. My husband is not too thrilled about the garden in the front either, but I think it will be better than having useless grass.

I was already planning on doing carrots and anything else that needs the depth on the deep side-luckily I cannot eat enough carrots! I am planning on backfilling the deep side a bit so that I don't put the expensive soil where it won't be used.

Any other suggestions are appreciated.

webchmura, I would love to see that condo complex, what a great use of space!!!