Hi Matt,
As you rightly mentioned São Paulo is the largest Brazilian producing state of avocados (4th largest world producer) by virtue of the fact that the modes of transportation and ease thereof favors the state greatly. I'm attaching a link to a site that deals with avocado farming in São Paulo and it lists the principal zones of production in the state. I'm sure it will help you narrow your search for land somewhat.
http://www.todafruta.com.br/portal/icNo … ticia=9462
You may want to check out some real estate websites to get an idea of prices too. One you could use is LUGAR CERTO you can search by state, city, etc. Click on the green bar comprar, check off the do RURAL below that, then you can enter the state, cities, area of the piece of land, etc., to narrow the search.
You were right about lack of financing being a roadblock. Firstly, none of the Brazilian banks provide financing to foreigners unless they are either individuals who are permanent residents or unless they are business entities registered in Brazil. I don't know if you could obtain financing from US banks to invest in property here, something you will need to check out.
The requirements for permanency with an Investor Visa are really quite uncomplicated and you will need a minimum investment of R$150,000 which is around USD $75,000, a business plan, declaration of area of operation and number of Brazilian jobs created, etc., to qualify.
This presents a couple of options that I can see right off hand. If you haven't all the money you want to invest in the venture perhaps you could find another individual or individuals each with 75K to invest but no idea of what to do and form a co-op of investors, I believe with individual investments each of the minimum you would each qualify for permanency. Lot's of people want to go that route to get permanent visas since it is really uncomplicated as compared to others. Who knows you may even be able to find interested individuals here on the blog. Try posting a thread seeking investing partners if you decide to go that route.
The second option is find out if with the appropriate permanent investment visa, the CNPJ (incorporation), state registration, etc. you could obtain financing through a Brazilian bank. Perhaps if you can then you might be able to arrange some bridging funds through a US financial institution.
Hope this helps you.
Cheers,
William James Woodward - Brazil Animator, Expat-blog