How much will it cost to get my car's brake system repaired?

I have a 1990 Honda Accord, that recently (in the last few days) started having problems. My mother was driving it, and failed to tell me that she was needing to refill the brake fluid several times within that period. We took it into a shop and had the car looked at. They said that the entire system would need to be replaced because brake fluid had leaked and gotten on everything. I know that I definitely can't afford the price they gave to get it replaced.

When we got it towed back to our house the driver referred us to another shop, and said they could do it for a lot less. I'm wary of both shops (one could be overcharging, the other could be giving bad service), but don't have many options. I'm wondering how much it would normally cost to replace the system, and if the entire thing actually needs to be replaced, or if there's a way to just replace what caused the leak and clean it up somehow.

I'm young and know next to nothing about cars, so if anyone is willing to give me some information it would be appreciated. I don't know how many of the repairs are necessary, and if they are what they should go for. Any help or information would be appreciated.

The pads are all that can be damaged by leaking brake fluid. There may be some damaged parts that need to be replaced to stop the leak. I would guess $100-$500 if the Honda parts are anywhere priced like good American parts.

Coated me $500