I've mentioned it in another thread sometime ago, but it should be said again:
The all in one Amiga's (ie the 500, 500+, 600, and 1200) are made with REALLY poor quality plastics that have become with brittle with age and heat form use. If you get one shipped to you make sure you have it loose wrapped in bubble wrap at least two inches thick (tightly wrapped seems to put stress on the case and keys), then boxed, and bubble wrapped again, then put in to a second box. Have all other parts shipped in another box. I went through several of them busting in half, cracked cases, and brittle keys popping off. All in well packed and none should have broken.
Commodore used the cheapest plastic they could on the all in one Amiga's as well as the C64c's (the second C64 in the white, Amiga looking case), and now its starting to haunt owners of those rigs. Oddly enough, Atari ST's are made with amazingly strong plastics that are as good today as the day they were made. I mention the Atari because they were run by Jack Tramiel after he left Commodore and he just might have been the cheapest man in the history of the earth. He would never pay a fraction of a cent for better plastic if he there was a cheaper option, yet many of Commodore's rigs are in really rough shape now while ST's are still chugging along like there were just made.
Still as an old Commodore junkie I still love the Amiga line, and can say that for a game rig the 500 is just fine. I have yet to stick a gotek in mine, and still use floppy's. There are a couple of projects in the works (cant find the links right now), that will be adding more RAM, IDE interface, and something else to the 500. Last a saw a few months ago, the project was near complete. I know it would require a wee bit of modding to tuck a 2.5" HDD inside the case, but no biggie. The chip ram expansion on many A500's is starting to become an issue for many as most of them had a real time clock/calendar with a battery backup. The issue is the batteries are dead and leaking on many of the expansions, and the vast majority of them require a use to desolder the old battery and solder in a new one by directly soldering to the battery. Not the safest thing for many who have never used a soldering iron before.
Then there is the display issues. Its not hard to hook an A500 up to a modern display, but it does require some extra bits, dongles, and adaptors that are bit of a hassle. Considering that most games on the Amiga were sprite based, they tend not to look their best on modern LCD's. If you can, its best to buy a quality RGB monitor like the 1084 or 1084-S. Those can cost twice the price of the computer if shipping prices are added in.
In the end, it does require some effort and money to get into retro Amiga's but not as much as it seems at first glance. The 1000 and 500 are going to be the hardest to get up and going and while the core systems can be had cheaper than any of the other Amiga's, they will cost more in money, time and effort to make into a good game rig. The 3000's are the best line if you can pay the upfront cost, as they are very easy to work with, backwards compatible with most 500 games, and pretty much ready to go out of the box, and easy to expand for other things like a Video Toaster. The 500+ are a fairly rare breed, and the 600's and 1200's are just way to costly when you consider the fact you can get the 2000's and 3000's for the same or less and they are simpler to work with. Dont even think of looking at the 4000 if money is something to consider. Then again, I'm in the US and those are pretty rare machines here so they tend to be a bit pricey.
Still worth it, and they are just going to keep going up in price. If the bug has bit you and you decide not to get one, then you will kick yourself in a couple years with the prices are double or tripple what they are now. I loved my Amiga's in the late 80's and early 90's. Sold and traded them off and regretted until I got back into them about 6-7 years ago. No longer have my plotter, external HDD, external CD-ROM drive, external floppy drives, or my homebrew robot lab for my old Amiga's. Those kinds of things are to hard to find and cost way to much now, but at least I can play great Amiga games they way they were meant to be played. Just an A500 with a 1MB chip ram expansion and a 1084-S monitor. Well worth it if you can skip the urge to expand the Amiga for a very limited number of games. Good luck with whatever you decide to get.