Hello
Have a question about 2 up offers - what are the maximum stakes that you can use?
Honestly, I have never tried to max it out. Most I do is £25
How much bankroll so you need to hit all of them with maximum stakes?
See above, but you will be betting on odds of around 1.5 to 3.0 so your exchange will need to reflect this. So not as much as if doing horses with big odds.
Second question - can you get totally banned from a bookmaker? ( not restricted but totally banned)
Yes. But you are more likely to get restricted to pennies or zero. Which is effectively the same thing.
If you "only" got gubbed - how much money can you get from gubbed accounts?
Once gubbed, you are on a hiding to nothing. Arbing will last a couple of weeks at most until you are restricted down to nothing. Sometimes its worth maintaining an account if they have good casino offers, but usually I just cash out and walk away once gubbed. Some people will tell you some bookies ungub but I've never known it.
I am planning to do 2 ups with Bet365 and Paddy as well, on maximum stakes.
Is barely (but still) 6 digit bankroll enough??
Depends how many matches you want to do at a time. (saturdays can get busy, for example) But I would think so. You can always start smaller and build up.
And also, is my money safe on those websites (compared to a bank for example). I would be anxious about depositing thousands of €€€ in there.
Regarding Paddy and Bet365, they have been around a long time and should be safe to deposit your money with. Same with the exchanges Smarkets and Betfair, which is where most of your capital will be tied up. I would be wary of leaving too much with lessor known bookmakers.
I do tend to find 2ups a bit over rated to be honest and have never made much from them, so I would look around at other offers too.