Have I got it wrong?

I have a Garmin Nuvi 2575. A reasonably cheap GPS. Bought in Thailand with Thai maps on it.

I was looking to add a UK / N Ireland map onto it for this summer. I know my way around technology and have pretty questionable morals so was looking to see if it can be done for free. It seems a right pain in the arse so then looked at buying the maps but they seem to cost a fortune; hundreds of pounds. That’s compared with a cheap unit costing >£70 on Amazon with the maps installed.

So,

a) can the maps be installed for free, easily?

b) if not, am I confused with the pricing or is it cheaper to buy a new unit than it is to buy a map?

Thanks

You can buy the Garmin City Navigator maps for UK and Ireland for about £30 (or about £40 for all of Europe). eg http://www.amazon.co.uk/Garmin-City-Navigator-Ireland-microSD/dp/B000L3APBK

Or if you have questionable morals, its easy enough to find the City Nav maps on Bittorrent etc…

Or you could download some OpenStreetMap based maps for free. eg from http://garmin.openstreetmap.nl/
Though they might not work quite as well for routing or searching for addresses.