I am leaving late September on my first round the world trip.

My plan is to travel Portugal - Vietnam, always by train. Explore a bit of SE Asia, and then to USA, where idealy I'd like to purchase a car, drive from W to E and sell the car.

I am planning to do this in 6/7 months, with the less money possible.

My biggest issue so far, is the VISAs!

Any tips?

Thank you

I traveled from Scotland to Saigon by rail back in 2004.

See: wilhelmswords.com/rtw2004/index.html

What route are you taking?

For train travel I have always found http://www.seat61.com the best resource. Not infallible, who is, but by far the best out there.

May help to get more info on visa stuff if you provide details of your nationality/ citizenship.

My main tip, after years of travelling is to travel light. You never need half the stuff you think you will (apart from money of course where the opposite is proably true.

www.hostelworld.com and www.hostelbookers are pretty good booking sites although it is easy enough to just to find somewhere on arrival in most places.

Learning a few words of the language of the places you are visiting goes a long way to endearing yourself to the local population. Even it is just hello, goodbye, please, thankyou and, of course, can I'd like a beer please..

I didn't notice the 'buy a car' thing the first time through. How do you propose to insure it?

Crellston, those sites are both fine for hostels, but if you just use Hostelz.com, when you put in your dates it has the ability to look to see which of those sites (and a bunch of other hostel sites) has the hostel at the cheapest rate. That's why people usually just use Hostelz.

Why not just rent a car? It couldn't be that much and would be easier than trying to buy a car and sell a car.

If you are not a US citizen and/or do not have a work permit here, you can't get car insurance, which is required to purchase a car in the US. I'd come up with a different plan. Buses are cheap and achieve the same result.

My style for travel across the US is to take an Amtrak train to a scenic destination and then rent a car. I make a loop with the car and then turn it in and take the train onward to the next destination and repeat.
You do have to have a US address to buy a car and insure it.
As for hostels I prefer Hosteling International hostels to the others I have stayed in.

Regarding visas, on my 6 month RTW, then another for 4 months, in some cases the only thing to do, given required timings for entering & leaving some countries, was to get those visas en route. For instance, a visa for China was obtained in Delhi, a visa for Burma in Vietnam. You'll need to know in advance what your route is likely to be, then where you might be to most easily obtain those visas. Keep in mind in some cases consulates may keep your passport for a week or so, so begin early in your visits as you'll be unable to cross borders during that time. It takes planning but isn't really difficult. Just leave yourself the time to accomplish what you need to do without stress.

Buses aren't bad to get around, we also have passenger trains in some areas in the US. Even renting a car will be doable as you are allowed to return it at different locations. This is pricier than returning to your original rental office, however if you were planning on buying a car, I think it'll still fair cheaper...

Airbnb is a great thing here, also couch surfing. It's really easy to find a cheap room with friendly hosts all over the place.

A strong suggestion is to make sure you check the weather during the times you plan on coming as the weather here has been crazy all over the country... Best times would probably be May-October for an even weather report for your cross country trip.

Hope that helps with the US part!