Personally I don't see the point for a soil test before buying. The reason being that, the soil will have to be amended either way, fruits don't have metals/minerals either good or bad (think lead/etc), and herbs are used in such tiny amounts, that heavy metals aren't really a huge concern. When it comes to vegetable production, esp on an intensive scale (single person, 2acres or less). It is almost a given that there will be alot of imported composts, straw, biochar, etc. So on the 1/2 acre example I gave most of that will be enriched soil and due to all the fertility and nutrients that you are extracting you will have to add carbon/compost/biochar/minerals after every harvest to make up for your export.
Also while the fruit trees mature you are able to plant alot of vegetables in that section.
By having such a neat farm you will be able to show so many people that alot can be done on a small farm, thus encouraging others to follow a similar path and thus eat more locally.
http://www.gardensofeden.org/04%20Crop%20Yield%20Verification.htm On just the 1/2acre vegetable section you will be able to sell 5,000lbs of harvest. It seems like the numbers can even be 3times that
http://urbanhomestead.org/about/by-the-numbers/
Iterations are fine, we don't have to be perfect
My 2nd Location:Florida HardinessZone:10 AHS:10 GDD:8500 Rainfall:2in/mth winter, 8in/mth summer, Soil:Sand pH8 Flat