I file them for a few clients of ours and I have to say I find them more trouble than they are worth. The most annoying thing for me is that they are more of a nuisence to log the filing dates and remember to do them than anything else.
If it is your first annual return and nothing has changed since incorporation then I would certainly do it myself. Bear in mind the following : If the formation agent formed the company for you, they might have held the issued shares first?, and if this is the case the previous shareholders and dates of transfer will have to be listed on the shares page along with the current shareholders if the share transfers took place within the past six months. I find that page is often where people make errors.
Other than that, just make sure everybodys name/address and details etc. are the exact same as listed on the original company package or the B1 will be sent back. If you are going in to the CRO to lodge it yourself, you could ask one of the counter staff to just flick through it for you, explain its your first return. I find most of the counter staff very helpful, but there are some jobsworths there too!!!
BTW €110 is not bad for filing an annual return.