Once you have found a car you like, (1) check that the person who sells it actually owns it, (2) check that no bank or loan company is listed ad having the car as security for a loan (online services exist for that, at least in AU), (3) check that it has not been registered as an insurance write-off in the past (also, online services for buying used cars often offer this check), (4) write a contract or use a standard form contract to ensure you have a document showing the date, odometer reading, names of parties, moneys paid... get signatures, (5) Importantly, ALWAYS get your own mechanical check done by an independent mechanic that you choose. Even if a car is sold with a safety certificate, you were not the customer of the mechanic who provided it and will have no recourse if anything goes wrong. Getting your own check will ensure that you are the person who pays for the service and who the mechanic has an obligation to. Again, here in AU, Auto Clubs offer mechanical checks for competitive prices. Don't be afraid to pay $150-250 for a mechanical check - it could save you thousands.

When it comes to finding good evidence-based information, books are best seen as starting points to provide you with a broad overview of a topic, so that you can then dive into academic journal articles about those elements of a topic that are most relevant for you or you are most interested in.

Generally, books by somebody who knows what they are talking about will be factual, and free from opinion, and statements will be supported in some way with scientific evidence / references. They will also be free from personal anecdotes and 'anecdotal evidence' (ie "after he used this miracle food, the diversity of her gut microbiota seems to have increased exponentially, so this food is fantastic" is not good data). Much like good journalism, you want a book that presents you with data in a structured and easy to understand way, but you don't want to waste your time reading about some person's 'opinion'. You can get an idea of what I mean by reading a couple of articles from your local newspaper, compared to a better news source like, say, The Guardian, where facts tend to be presented without the author's subjective view or interpretation.

My approach would be to find out which universities are well known for exceptional research or training in the field you'd like to learn about, then find the reading lists for relevant subjects at that university. Or you might write to a lecturer or two and ask for their recommendations. That should give you a starting point.

You can also search for books written by professors associated with a well-respected uni, and decide which of those you feel are most authoritative to write about a given topic.

Keep in mind though that all books, by their nature, will contain 'old' information. It takes time for a book to be written, edited and published. By the time it is available, there is a very good chance that some information it contains will be outdated - maybe improved upon, no longer 'best practice', proven to be false, etc. So, books are great resources, but limited in their usefulness depending on what level of knowledge you're looking to gain.

Academic journals can be more accurate and contain much more recent information than books. Google Scholar is a fantastic resource for finding journal articles. You'll still need to work out which articles are great and which are rubbish, but you won't need to deal with as much pop pseudo-science and quackery as you'll find at your local bookstore. And, you'll find more recent information with greater specificity. If an article is not available for free, email the author and ask if they would email it to you - most will be happy to.

Happy learning!