ummm 50k it would be crazy not to take the money. However it would depend on what the house looks like, if it is a old junker...the money for sure. If it was brand new and looked classy than the house. However i'd just take the 50k and move to where i want to than use the rest to buy a home i'd actually want, which makes more sense to me than accepting a old nasty house i wouldn't even want just because it's free. For me to take something i actually have to like it, just because it's free don't mean it's great and i should take it.
I'd definitely rather have a free house with no mortgage! But then again, it also depends where this free house has to be....if it's a house that I don't want to live in or if it's in a place I don't want to live and if it's not going to turn over a profit (if I sell it), then I'd take the $50K. :)
Ok, in the U.S., I'm changing my answer. If I win, say the HGTV Dream Home, and say, it's a million dollars, I have to pay income taxes on a million dollars. So I have to take out a new, bigger mortgage to pay the taxes. Or try to sell an expensive house in a slow market. (The extra money they give you doesn't cover all the taxes, plus you have to pay tax on that money and the car too.)
If I win $50k, I just pay the income taxes out of the $50k. Life is simpler, and I can get a new kitchen. I'd take the $50k.