If there's one new periferal for the Amiga 500 I can recommend without hesitation it's the ACA500+ from Individual Computers. Among the specifications is 8MB RAM, 2 Compacr Flash connectors and a few expansion ports. One can be used to connect a Amiga 1200 expansion, e.g. an accelerator card. I have connected a Blizzard 1230 IV and it works like a charm. Price is € 135,00 which I think is very affordable; bang for the bucks!
But... Individual Computers does not recommend this setup. Use in an A1000 is not supported and could damage the ACA500+. You've been warned!
I got a spare edge connector from some nice Italian guy and I soldered it in. It works perfectly!
I also bought a replacement MFM harddisk via someone at A1k.org. I got it to work after many tries by circumventing bad sectors on the Amiga partition. As the MS-DOS-partition avoids these automaticaly, the Amiga apperently does not. So I chose the cylinders that are not bad for the Amiga side. The partition is quite small, but it works well now.
A long time ago I bought an Amiga 1000 with a A1060 Sidecar. A Sidecar is a complete PC XT-clone made by Commodore. It has it's own housing that is attached to the side expansion bus of the A1000 and uses its periferals. The unit I bought had a hardcard in it: an MFM-controller card with harddisk. It worked perfect. But it doesn't anymore. I bought another one, but the disk only worked once.
This picture is not mine. I took it from https://compidiaries.files.wordpress.com.
The harddisk stopped working and the many times I attached/detached the Sidecar to the A1000 trying to get it working again has made the connector fail. One or more legs of the 86 pin edge connector do not make contact and aren't easy to repair. A new edge connector is rare and expensive. Only Digikey has some to offer but you pay almost € 70,00! So I put up a Wanted ad on Amibay.com and now I will get a desoldered connector from some guy in Italy.
Another problem of the A1060 was the 360kB 5-1/4 inch floppy drive. I didn't know if it was working because I didn't have MS-DOS system disks in 5-1/4 inch. I now managed to get a drive and attach it to an older PC. After much trial and error I now have a system disk to boot the Sidecar once it is repaired.
On the picture the board with connector desoldered.
To be continued.
The arrow-down key of my Amiga 1000 keyboard (Mitsumi made) didn't work. So I dismantled the keyboard and discovered that one of the legs of the key was broken. The legs are soldered to the PCB, but are quite easy to remove. The mechanism can then be opened and repaired.
These pictures are not mine. I took them from https://geekhack.org/index.php?topic=19761.30
I took the oportunity to remove all keycaps and clean them. I also retrobrighted the housing of the keyboard and the space-bar. They were yellowed a lot.
Today I installed one of those RAM expansions for the Amiga 500/1000/2000 made by Kipper2k. I thin they are absolutely great. Not only you get 4 or 8 MB Fast RAM, but you also get a IDE-CF adapter that you can use as a solid state harddisk. You can't recognize your A500 after you installed this. Recommended!
You can get this fine piece of hardware here.