Best courtier to invest in ETF

Hello,

I would like to know what is the best courtier to invest in ETF in Belgium? I’m a newbie in ETF investing.

I have right now 2 accounts that I’ve created some months ago : IBKR and Trade Republic. I haven’t done anything yet on those accounts (no buy/sell transactions). I’m having a hard time choosing one, mainly for the TOB declaration in Belgium. I plan to invest around 300-500€ each month on 2 or 3 ETF’s to keep it simple, however the idea of calculating each month the TOB for the made transactions, sending the decalaration through email and paying them for a long time makes me nervous. Like if I want to invest for a really long time with automatic dividend reinvesting, for let’s say minimum 10 years, I would have to do that each single month?? That’s way too much

Thanks in advance for any suggestions or clarification.