Havent been there in a couple of years, and I think they might even be on euro now, but I think if you search just a little, Prague can still be a good value. And things should be pretty cheap elsewhere in the country.
Romania is definitely cheaper, but its not very close to Prague, especially for only 6 days. Budapest is more expensive. Poland is nice, but not a great deal cheaper either.
Slovak Repub sounds like the best choice for you, its quite cheap, has less tourists, good mountains, and several interesting, small/med sized towns in the western half of the country.

If you don’t mind hostels, then Prague is still very affordable. Hostels can be had for $20 a night, and beer is still pretty cheap. Good local food away from tourist areas is still very cheap and delicious. Also, lots of local theatre and music which is affordable as well, as long as not too touristy. Bus and train travel still affordable as well, so you can do some day trips to Kutna Hora, or an overnight to Cesky Kromlov, which also has some reasonable accommodations. Enjoy.

Romania should be the cheapest.

BTW, Transylvania is a region of Romania.

Debra Nuñez wrote:

We are getting a free flight to Prague, but have very low funds esp. with the US dollar and we’ll need to head off to a less expensive chountry. We will have 6 days to travel and have been thinking of Hungary, Romania, Slovakia,or Transylvania. Any info.on which country our dollars will last the longest and also which country you have experienced? All info. most graciously appreciated Debra

The cheapest will be Slovakia and Romania, but Hungary and Czech rep. won’t be THAT MUCH more expensive. But you’re talking about visiting 4 countries in 6 days, that’s not doable. Just the train ticket from Prague to Brasov (in the Romanian region of Transylvania) will cost you about 100 euros per person. The best value (low prices, civilized service) will probably be Slovakia.

I suggest you center on Czech republic and Slovakia, maybe with a trip to Budapest. Use buses, not trains. What do you want to see? Historical architecture? Nightlife? Natural beauties, scenic trips? Eating? Spas? And also, what exactly are “very low funds”, how many US dollars per person and day? If you specify, I’ll be able to give more precise suggestions.

Slovakia will be on euro since 2009, but the other three still use and will use their local currencies. Anyway, one night in Prague can be had for as little as 200 CZK, which is about 13 US dollars. For example here: http://www.studentho… or here http://www.suz.cvut…. – but for a nice room be prepared to pay about 400 CZK, which is about 25 dollars, per night per person. Not that bad either.