Although the gold amounts for Mag and All bosses in Kara have been nerfed there are still plenty of very easy soloable bosses that can be done by anyone with decent tanking gear. Your best bet is to have a dps offspec and a tanking or soloing spec whichever you prefer to allow you to clear trash faster and some bosses are actually easier to kill in dps gear / spec.
I am going to cover a couple of really easy kills and provide details as well as videos that will provide a visual understanding to how to solo these old content bosses. These will not all be in this post but will come later on.
First we will take a look at Hydross the Unstable he is the first boss in Serpentshrine Cavern.
The trash leading up to him can easily be handled in dps spec the do drop Coilfang Armaments which are used to gain rep and do a quest while leveling so check the AH you can actually grab 20g a piece for these and should pick up about 5 leading up to the boss. The boss itself is simple enough to solo and you will get 250g dropped as well as another 20-40g in vendor epics. For a guide on how to solo him watch this video.
Soloing Hydross should take no longer than15minutes to kill him and the trash, once hes dead you will be up 300-350g this is not bad money at all.I will post more easy to solo bosses that provide a lot of gold in the next couple of days, stay tuned.
-Cheers and good luck