Boatnewbie

Complete newbie in my 50s. We're looking at buying a boat for the first time as have come into a bit of money and want to enjoy some long weekends, etc doing this while we can. What do we need to look for when buying? We would like to be able to go to the boat for the odd weekend and stay over (maybe with a couple of friends) so would like one berth and maybe space for a sofabed. Please tell me about moorings. Presumably we'd need to pay to have a permanent mooring but what happens when you travel on your boat - are you allowed to moor anywhere or do you pay at different places? Also what licences do you need and insurance? Is there anything else I should think about? And what should I think about when looking at boats? Are there any other costs I need to think about? I've been looking at what's for sale to get some idea of what we might like (budget around £20-50k). Personally I like the traditional narrowboats or Dutch barges but my partner prefers the more modern cruisers (is that the right word?). We are not at the age to undertake a project (and don't have the skills) so would like one we can use straight away that has facilities (a shower is a must for me!) All advice very grateful. Thanks in advance.