Can one assume that you own this property? If so, there is almost no way that an attractive garden will not increase the value of the property more than the cost.

The first thing to do is draw large outline of each prospective garden area and make several copies.

Do as much research as you can and get ideas from magazines and websites. Adapt what you see to your area and do some improvisation.

A simple ornamental garden in front keeps passers-by from swiping the veggies.

The backyard could be built around walkways and raised planter boxes for veggies.

There is a European traditional style based on a "wagon spoke" design with a central feature such as a sun dial.