Ric, started off with one, put it with a Management Company for a Year, You need a Buy to Let Mortgage (if you need to borrow) and Landlord's Insurance (different Companies, different names).
In the first year we spoke to a lot of Landlords and Management Companies to get as much info as we could, amazing what people tell you if they think there's money in it, then went Solo, 9 maybe 10 years down the line we've not had any real problems, one bad Tenant (drink related) and he took the easy option and walked away.
The one we just sold was Number 6, (all 3 bed semi's) we're looking to get everything closer to home, as tenants move out we'll sell and replace, I really don't want to drive 20+ miles at 0200hrs if someone has a burst pipe or something similar.
Research your potential market, buy carefully, have the right insurance and it can be very rewarding, Good luck!