A tourist visa allows you to stay for 28 days in Myanmar. You must stay in a government approved hotel for tourists and you cannot be involved in commercial activities.
Take note that it is possible to apply for Myanmar tourist visa electronically via the Ministry of Immigration and Population website. You should be able to get your tourist visa application approved within 5 days.
If you intend to explore investment opportunities in Myanmar and may stay for more than 28 days and possibly stay at the home of a friend or in a company-rented apartment in Myanmar then you need to apply for a business visa. A business visa allows you to stay in Myanmar for up to 70 days, you do not have to stay in a government approved hotel, you can be involved in commercial activities like opening a bank account, renting a service apartment or office, put down a deposit to register a company,etc.