Deposit bonuses: percentage, base, ceiling
A deposit match has three moving parts: the percentage (100% doubles your deposit), the ceiling (up to €200 means €200 of bonus at most, however much you pay in) and — decisive and least advertised — the wagering base. A 35× requirement applied to the bonus alone is half the turnover of the same 35× applied to deposit plus bonus. Two offers with identical banners routinely differ twofold in real cost; the cards on this page state the base explicitly so you compare like with like.
Play them with the ceiling in mind
Deposit exactly what the offer optimises for: paying €500 into a "100% up to €200" bonus wagers your whole balance for the same €200 everyone else got. Check the maximum bet while wagering (commonly €5 — a breach voids most bonuses), the game weighting if you ever leave slots, and the clock against your real playing volume. And when the terms fail those checks, deposit without the bonus — a withdrawable balance from spin one is also a bonus, paid in flexibility.