I like 100/300/300/80/20 for .50/1/5/25/100 so 800 chips because I like to have more $1s in play.
I think the standard is 100/200/300/80/20 so 700 chips and this will work just fine.
Smallest set might be 80/160/300/40/20 so 600 chips with bank of $4700 allowing 2 x $200 buyins for 8 players at .50/1
Let's say you want to keep your set to 400 chips (which is pretty small, but might be adequate). 8 people buying in for $100 at a time, maybe your total amount of money on the table at the end of the night hits $1600.
40x $20 or $25
Total bank $1930-2130. As the game grows, add $5s and $20/25s as needed to increase your bank. Even if you go to 10 players, you won't need more than 100 fracs, but you should look to increase total chip count to 500 or 600.
100 fracs is fine.
200 1s is the most you usually would need. Plays great at 0.5/1 or as 1/2.
200 5s should be your minimum. Having more 5s is always fun if your budget allows for it and if your game grows.
If you want to keep it to an even number 80 - 25s and 20 - 100s.