Thinking of purchasing a $300 GFA 555 after reading a lot of positive reviews but have also been warned it might be getting close to having to change the caps on it.

Any idea on how much that would cost?

Also, do you know how it compares to a Hafler DH-500?

Just the age of the amp?

If you DIY then the cost is very low, just the cost of the caps and then it's a question of whether you go for ordinary or some premium audiophile brand.

I can put together a computer and might be able to solder, but I know nothing of electronics, resistances and that kind of stuff.

Seems I shouldn't even worry about it?

The Adcom and Halfer are very different animals. The Adcom is a very typical solid state offering. Lots of power and clout, but not the last word in transparency and emotive prowess. The Hafler is a more refined device with a sweeter delivery and much more character. Not enormously dynamic and detailed, but ultimately likely to sound more interesting with today's typically forward-sounding speakers.

If the owner claims the caps might need replacing, run a mile from it (it might not be the caps that are the problem). If the general (intranet) consensus is the caps often need replacing, run a mile from it. Not so bad for some fanatical DIYers maybe, but otherwise not worth buying if you have to repair it as soon as you get it. Which is exactly what it is. If a part is not working optimally, the product is defective.

Hafler products aren't known for being great used buys (also reliability liabilities..) so if I were you I'd look elsewhere.
What's the rest of your system?

or Haflers. You got me confused there in the end.

I already have the Hafler but was a bit disappointed when paired with an old NAD pre-amp and some Infinity RS 1.5 (old skool.)

So I saw an Adcom on sale around here for $300 and thought I'd test it out.

It was just one guy saying that at 30 years old, replacing caps would be a very good possibility. So I just wanted to get an estimate just in case...

If the Adcom is not as refined as the Hafler, I won't be happy with the Adcom either.

Thanks for your good comparison.

A 30 year old amp is likely to be a far cry from what it once was. It probably won't just be the caps that need replacing.

Getting pre-amps and power amps from different stables to marry can be a very difficult thing. You're Hafler may not necessarily be the culprit here.

Why not just go for an integrated or a NAD power amp?

Very nice, subtle but powerful amp. Heavily biased into class A hence the musical subtlety.

The only problem with it was trying to replace it, for some reason I wanted to upgrade but struggled to find something better. Ended up with tubes.

and how they all compliment each other. It could be there is may be a pre and power amp mis-match here. Or an amp/speaker mis-match.