Hi Boo,
Much like you I'll be working to a very tight budget to become a liveaboard. I'll be looking at £25k max (and that has to include survey and any extras I might need to get us started). But I've given myself a good year to realise the dream (and pursuade my boyfriend that it really is a good idea to sell all our crap and live in a floating sardine tin ) and hopefully a bargain boat will come along in that time.
But because there's the two of us we will need some space - ideally the basics of a fixed double berth, showeroom, galley and living area PLUS one extra "cabin" that can be used as a study or a reading room. Whether that extra space turns out to be just a covered cratch area or squeezed around the engine on a trad, who knows?! 50ft + is a lot to ask for not-much-money but we will need it. We're not in a hurry and can bide our time as necessary. The layout of the boat will be as/more important than the length - as a giant open-planned nb won't enable us to "compartmentalise" and have a bit of privacy when we need it.
We don't mind getting something a bit dated as long as the hull's sound and we have hot water and heating, a cooker and a fridge. The rest we can slowly work on. I'm a dab hand at making/fixing/painting/tinkering/ diy (once made a giant IKEA wardrobe on my own and moved it into position only to read the instructions later to find that it should have been tackled by a minimum of 3 people!). Although I have to admit unlike your multi-talented-self, Kev and I have zero welding/metal/engine/wood working skills at all. But his dad's a carpenter and a classic car/motorbike fanatic and had a boat for years, and my dad was an electrician so we may be able to draw on their talents a bit. I'm a great one for if I don't know how to do something, I'll bloomin' learn how myself! Hope that plus a lot of enthusiam will be enough to get us started!?
Here's hoping... and searching the classifieds... and browsing these fine pages for inspiration and advice, of course.
Good luck with finding your bargain.
L