Here are some words and expressions you can use to talk about advantages and disadvantages:

• It’s cheap and, what’s more (in addition) , it’s reliable.

Not only is it cheap, it’s also reliable.

• It’s cheap, but, on the other hand, it’s unreliable.

Whereas X is cheap, Y is more expensive.

Although (even though) it’s expensive, it’s not very reliable.

Despite (In spite of) the price, it’s not very reliable.

• Is it cheap? No, on the contrary, it’s expensive.

• X, unlike Y, is very good value.

• It’s not reliable and in any case, (besides) it’s too expensive.

• It’s too expensive. However, we have a cheaper model.

• It’s very expensive. Nevertheless, I’ll consider it.

• I want a guarantee. Otherwise, I won’t buy it.

Whatever you say, I won’t buy it.