As always, we will start with the positives. The Bolivian people are very nice. It is not a violent country. People will try to help you, although it is useful if you speak Spanish because outside tourist destinations virtually no English is spoken. Bolivia is an absolutely fascinating country, easily meriting two to three weeks of tourist travel that will leave you agog.
So what on earth can be wrong with a country full of friendly people and interesting places to visit? We must start somewhere. So let us start with your arrival. Bolivia is not bureaucratic; the problems are of a different kind.
La Paz airport is at 4050m above sea level. Aeroplanes need specially reinforced tyres to land there. You will be subject to moderate to severe altitude sickness as soon as you arrive; you may just fall over with a dizzy head as soon as you try to collect your luggage. This lasts for several days and it is extremely unpleasant unless your body is accustomed to altitude sickness.
There is a full span of hotels of varying quality and price in La Paz, but less so in the rest of the country. In La Paz, the hotels at the bottom of the hill upon which La Paz is built are more expensive because the altitude sickness is less severe. However the real problem with the majority of hotels in Bolivia is the electrical wiring in the bathroom, and you will soon learn about this the hard way. There are no hot water tanks; hot water is generated by running the mains current through the metallic shower head (for example). There will typically be a large electrical switch of the kind used in death penalty chambers, covered in masking tape, in the bathroom. The order of events to take a shower is (a) direct the shower head where you want it; (b) turn on the (ice cold) water; (c) flick the giant electrical switch (only touching the masking tape); (d) shower with warm water without touching anything metallic while doing so; (e) flick the electrical switch back off (again only touching the masking tape); (f) turn off the water tap; (g) leave the bathroom. When you get this wrong (and you will), the effect is like sticking your fingers into an AC mains plug on the wall. If you have heart problems, it may kill you.
Cocaine is not just de facto legal in Bolivia but de facto free. Several bars in La Paz (you must work out which ones yourself if you want this sort of entertainment) have large piles of cocaine on plates on the bar or tables, with a series of straws for the alcohol-purchasing customers to enjoy at their leisure, a bit like a complimentary tray of nuts in an English pub. If you elect to indulge, you must stay constantly aware that the free cocaine provided openly on plates is sufficient to kill several dozen men through immediate cardiac arrest. Even if you are modest in your consumption, you might find yourself with a severe cocaine addiction, staying in La Paz, within just a few days. Do not indulge! It may seem tempting but it is highly foolish and just because all the wealthy Bolivians are doing it relentlessly doesn't make it any the wiser.
The unofficial guided tours of La Paz prison by inmates who bribe the guards to let it continue are harmless and fascinating. But do not buy anything (i.e. cocaine) from the inmates while in there or you will be promptly arrested walking down the street afterwards. (Purchase of cocaine to take away in Bolivia is generally dangerous; you stand a high chance of it being a sting leading to your arrest and the extortion of money from you.)
Be aware that a lot of Bolivian people defecate openly in the street, even in downtown La Paz. Be careful what you step in. Wear strong shoes and trousers that cannot easily be stained.
The Bolivian jungle and pampas (low-altitude sea level jungle and associated plains) is one of the most fascinating things in the world but any traveller into its interior is highly likely to become infected with several tropical diseases. It is possibly the most dangerous jungle territory in the world in terms of chances of being infected / poisoned etc by natural causes per unit time spent there. Read our article on jungle infections, animals and dangers before travelling. Taking a several day walk through the Bolivian jungle is madness. If you do it, immediately go to see a specialist doctor in tropical diseases at the end of the trip, for a full check up. Remember: just like the cocaine plates, just because other people are doing it does not entail that it is safe or wise.
There are cities in Bolivia higher than the capital. Potosi, with parts of the city reaching as high as 4,300 metres, is the highest city in the world. Do not attempt to travel there until you have spent several days acclimatising in La Paz; or you may suffer from acute altitude sickness.
Be particularly careful over what you eat in Bolivia. Food hygiene standards are very bad. Go into the kitchen. Explain to the cook that all water must be boiled for 10 minutes and all meat must be cooked until none of it is pink. Do not consume raw fruit or vegetables apart from fruit with thick skins that have been peeled by you.
Although it is easy to meet people who will propose to pay you to be a drugs mule; and although La Paz's relaxed air towards the consumption of cocaine can be beguiling, virtually every one of these proposals is a sting. You do not want to find yourself with a decades-long Bolivian prison sentence. The money you were offered is imaginery.
The country has simmering underlying ethnic tensions that can result in hidden violence. Do not get too close to any person or group of people who appear to want to make friends with you. Their intentions may be to embroil you in some mess. Be astute.
Bolivian travel is sufficiently rough that a person with a serious health condition should not travel there. Access to specialist medical treatment in an emergency is not straightforward. The country has very few doctors specialising in typical western ailments.
Bolivia is one of the most interesting countries in the world. As long as you follow the advice above scrupulously, you will have a superb and fascinating time. Just take care!