I'm going to be flying to the British Isles in a few months, and want to see three cities: Edinburgh, London, and Dublin. I considered getting a 3 leg booking, but for some reason it's extremely expensive - over double - to do so. Part of the reason being that Ireland is very cheap to fly to.
- Chicago <-> Dublin: $800 rt
- Dublin <-> London: $160 rt (around the same for Edinburgh, and about the same one-way from either, maybe $200 total)
- Chicago <-> London: $1000 rt (similar for Edinburgh)
- Chicago -> London -> Edinburgh -> Dublin -> Chicago: $2200 (!!)
These are all on "major" airlines direct from the airline (Aer Lingus or British Airways), I'm not travelling on Ryanair or chancing it on one of the shady ticket resellers.
Given the prices, I clearly prefer the Dublin round trip and then the separate price to London/from Edinburgh or reverse.
My question is, what's the best way to book this all told? Should I try to book all on the same airline, or book intentionally on separate airlines - or just pick the cheaper/simplest flights and not worry about it? I likely will stay in Dublin the first leg, so the return trip (London -> Dublin -> Chicago) would be all in the same day. If I book both tickets (separately) on British Airways, for example, will they forward my luggage if I ask them to, or will I need to deplane, pick up luggage, re-check, etc.? (Perhaps customs requires this anyway, I'm not familiar with UK/Ireland rules.) Will the airline notice I'm booking effectively a connecting flight and object (thinking I'm trying to get around paying the normal higher fare - which I sort of am, but I'm actually wanting to visit Dublin anyway, otherwise I probably wouldn't bother)?
American citizen, if relevant. I'll be travelling with my wife and two young children, also if relevant. Also, while not the main focus of the question, if there are suggestions on airlines (particularly Aer Lingus vs. British Airways, which seem the main two possibilities) they're welcomed.