Reading some threads about capital one it seems you can have two cards.
I have cap one platinum with a reasonable rate of 26.4% but only a £500 limit after 9 months of careful use. My credit is getting better and HSBC has upgraded my acc.
I used mse credit card guide and it said I was 100% for another cap one plat card 28.9 or classic with 34.9% but 4 months 0% on purchases so I went for that and got £1000 limit.
Reading some threads you might be able to merge the accounts but I assume I wont get the 26.4 on £1500?
The other card I have paid off is a marbles with £300 limit but its 54.9 so I have stopped using it and just have it for emergencies. I wouldn’t advise people get a marbles card as a borrow £100 on it and they cranked the apr up from 34.9 to 54.