This is going to vary tremendously from country to country (and even from state to state, in some cases). In general, though:
- Easy to form: requires little, or limited, paperwork and you'll register directly as a taxpayer;
- Difficult to sell: it is much harder to sell a sole proprietorship (or manage successsion planning, inheritence, that sort of thing) - you end up selling your assets but cannot sell the legal structure (since contracts and legal responsibilities will be in the owner's name);
- Taxable deductions limited: because your salary and the business' profits are the same, you'll find it difficult to keep savings in reserve for capital growth as you'll be paying taxes at a higher rate.
- Administrative overhead: depending on local laws, even a small company may be required to submit to a statutory annual audit or financial review, you'll also find this obligates you to keeping financial records (this is not, necessarily, a bad thing);
- Separation of interests: it's always a good idea to have a separate bank account and structure for a business, an LLC imposes this on the owner - and, yes, this does mean that the LLC can own both fixed and moveable property (like a car);
- Financial planning: an LLC allows you to pay yourself a proper salary as well as to save additional profits for capital growth; this should result in a lower overall cost of taxation as you can also pay yourself dividends from the unallocated profits;
- Easy succession planning: selling an LLC is as simple as setting a price and changing the share-ownership; the new owner buys existing contractual and legal rights by virtue of owning the company.
There are a lot of permutations depending on local law. One thing that isn't actually much of an advantage is the "limited liability" component of the LLC. Simply put: for a really small company the majority shareholders are usually going to be "forced" to stand surety for the company in their personal capacity.
Limited liability only becomes available once the company has quite a lot of cash/assets (or the illusion of a lot of cash/assets).
Update - noticed two further questions that appear very similar:
- What are the benefits and downsides to an LLC vs. Sole Proprietorship vs. Individiual?
- Sole proprietorship or LLC?
Should all of these be merged?