Deposit Protection Scheme

As a prospective landlord thinking it might be less of a ball-ache using an agent than going it alone...would it? Is the service worth my 7-11%?

Assuming you use a decent agent then yes, there is a lot of responsibility involved in being a landlord these days and more laws than ever to comply with, so it can often be far less stressful just to hand all the responsibility (or most of it) over to a third party, it also depends if you get them to provide a let only service or full management, full management can remove pretty much all the hassle entirely
(apart from occasional financial expenditure for maintenance issues obviously).
If you wanna PM me the area your property is in i'll shoot you back some links to some good agents in your area.