A couple of my friends want to start this lifestyle but are afraid to cuz of money issues.
Is it okay to do like raw tip lunch since rice and potatoes are so much cheaper where i live?
One of them is trying to lose weight and the other is trying to maintain their weight.
Would this kind of lifestyle work well for them?
Sure, any high carb vegan diet will result in great health. I'd recommend eating sweet food for lunch still just to get that quick sugar energy. Things like juice, dried fruit, winter squash, or sweet potato would be best.
Yes, it'll still work wonders.
How many calories would you recommend for lunch and dinner?
Eat until you are satiated. For me that usually means about 800 for lunch and 1000-1500 for dinner.