My house is free from termites, will my house get infected by termites in the future?

I just bought 20 years old house and I have ask professional to check on the house. It is termites free. I 'm contemplating weather I should spend 3.5k to do termites prevention treatment. Is the house prone to termites in the future if I don't do the treatment?

View this post on my blog: http://madeinhome.info/my-house-is-free-from-termites-will-my-house-get-infected-by-termites-in-the-future