Hi - sorry that you haven't had any replies but you asked a really hard question!
There isn't a lot of money around at the moment and my own personal opinion is that it would be hard to get started as a furniture maker. There is so much cheap and second-hand furniture around this area - and you have Ikea in Murcia too. I know that hand-crafted furniture is a completely different proposition but when people can buy cheap and cheeful then the quality market can be hard going.
There is also the cost of starting your own business here as you pay Social Security from day one, even when you are not earning a cent. You will also need an accountant as the laws here as pretty complex.
Sorry to sound so negative, but hopefully when things start to improve again there will be more money going around for quality products like these.
Good luck whatever you decide to do.