How investment works when the entrepreneur is a foreigner?

I'm a foreign entrepreneur, If a US investor shows interest in investing in my company.

1. At what stage do i have to meet them?
2. do you think it's worth it to spend $2000 in travel expenses and yet it's not guaranteed to get funding?
3. What if i even had to repeat spending that for multiple investors?
4. If i had a partner who lives in the US, Is he enough to get funding for us alone?

I am also a a foreign (South Korean) entrepreneur and was looking for investors in both South Korea and the US. Most of our members are college students in the US and we are planning to deploy a service starting in Korea and then US West. My suggestions are based on my personal experience.

Question 1. At what stage do I have to meet them? It depends but I believe frequent contacts do not harm you as long as most of prototypes and concepts are ready. We were not ready in prototypes when we started to talk with investors, but at least we had concrete concepts and fairly great profit model. As a result, we are about half-way to getting investments.

Question 2. do you think it's worth it to spend $2000 in travel expenses and yet it's not guaranteed to get funding? I think that's risky to spend a big money on that.
Some investors are generous enough to have video conference, so you could suggest that.
All the members in my startup are scattered out in South Korea, US Central, and US East.
So it was hard for us to meet at the same time in the same place.

As a result, we have been using emails with the investors and will have video conferences.
So far, they say it is highly likely for us to get funded.
As long as your startup idea is great, I don't think it's crucial you need to spend travel expenses.

Question 3. What if i even had to repeat spending that for multiple investors? Since money can be an issue, we kept looking for investors who we could meet through video conferences. I would physically visit to them if the progress is almost finalized.

Question 4. If i had a partner who lives in the US, Is he enough to get funding for us alone? I am not exactly sure what you mean by 'who lives in the US'. But I saw a few cases who live in the US as a foreigner (not a green card holder) and get funded by US investors.

1. You should establish relationships with investors as early as possible. Deals are formed over the course of months because investors like to know the people behind the companies. If you don't have any common connections then you'll have to build the relationship from scratch. The best way to do this is to send regular updates on your progress to investors who have shown some interest in your business. However, you must not blindly pitch your idea to every investor you can find in your favorite search engine. Pick the ones who are interested in your industry and ask them for advice about your project. That will open the door wider than a cold pitch email.
2. No, it's foolish to spend money to travel just to get introduced or meet for the first time. Spend it only when you're invited to pitch. When on a trip, try to hit as many birds with one stone as you can - meet with potential customers and partners, too.
3. Investors realize you're coming from afar. They will work with around your schedule if they're truly interested, so pack as many meetings into one trip as possible & don't limit yourself just to investors (yes, I'm repeating myself because this is important). If an investor refuses to work with your schedule, leave them - they don't respect you enough but pretend to be busy.
4. A co-founder's residence isn't the decisive factor for investment. The country of incorporation, the size of the market where you operate, investors' expertise in the industry & the market, and any special laws about ownership & foreign investment are far more important. No foreign investor is going to give you money to run an operation in a low-profitability market or in an industry they don't know or if there's no protection against you taking the money and running away to some safe haven where they can't sue you.

Try reaching out to Zemanta guys for advice. They're from Slovenia but US firms invested in them and they now have 3 legal addresses in 3 different countries (Slovenia, the UK, and the USA).