Things for grant applicants to remember about living expenses

• You will likely be responsible for paying taxes on your grant / stipend, and this will probably be significantly higher than taxes you would pay as an employee (because a self-employed worker makes both the employer and the employee contributions.) This may be due quarterly. Check the website of the tax agency in your country - "self employment tax" may be a useful search term.
• If you live in the US or another country without national healthcare, will you need to get your own health insurance? If you are on your parents’ insurance in the US, remember that ends when you turn 26.
• Might you need additional private care not covered by your insurance or national healthcare system?
• Will you need to make payments on student loans or other loans?
• Will you have enough to cover not just basic living costs, but some amount of unplanned expenses like medical bills or car repair?
• Will you need work equipment like a laptop or a standing desk?
• Will your project involve travel?
• Consider getting short-term disability insurance. (You might search for “self employed short term disability.”) This would provide income for around 1-6 months if you can’t work because of illness, surgery, mental illness, or giving birth. Importantly, most policies only cover pregnancy if you start the policy before you are pregnant. Many employers also don’t provide paid leave if you started the job recently. So for example if you plan to have a baby in about a year and don’t expect to get paid parental leave from an employer, you might want to get short-term disability insurance early, because most policies won’t cover pregnancy-related leave for the first 9 or 12 months.

• advice in the comments on this post.
• edited to add: more info on grants from Anti Entropy.