To make one is easy: 4 wooden pallets attached to each other by large hinges, bought in any DIY store. Nail these together. Cover with old carpet.
A good alternative is a large square incinerator, the type that look a bit like a cage. Line this with tough plastic, and cover with carpet.
We compost everything possible, emptying it into a homemade compost bin and covered with an old carpet. The carpet serves two purposes: one extra heat, two cats like sitting on it and so deter rats etc. Incidentally apparently its unwise to compost either apples or parsnips as both are favoured by rats.
As for garlic, planted randomly amongst lettuces etc it helps deter rabbits.
French marigolds help with aphids as does a plant nicknamed Fried Egg Plant (I don't remember its proper name)
I hadn't realised this discussion board existed before today ~ looks interesting.
Re: Orange flowers ~ Mimulus are lovely to look at, and great in hanging baskets, they last quite well and the range of colors, especially in the mixed varieteis, look really pretty.