Am a zimbabwean businessman currently residing in South Africa and would like to visit Spain for 6 days but have never been there before. I need assistance in getting accomodation which is nice but cheap and help on visiting historical, social and entertaining places.
I assume all your documents are in order? As to accommodation, there is a good number of hostels in town with prices starting at around €15 pppn. Did you already discover this website's accommodation service?
I wouldn't spend my entire six days in Valencia; two imo is more than enough. Valencia is pretty central, so you could decide to visit either Madrid, Barcelona or Murcia. Spanish trains are sort of expensive, but busses are all right.
In order to find accomodation in Valencia or any other city in Spain I use to check two different sites www.booking.com and www.muchoviaje.com being the first one of the biggest international reservation sites and the second the strongest national one you should be able to get the best prices.
About Valencia, you could spend two days visiting the city, the gothic quartier "Barrio del Carmen" is a jewel of the late medieval times in Europe, and the CAC "City of Arts and Science" is maybe the best modern architectural complex in the world. Other great areas are the Gran Via, "poshest" area of the city, Bull fight arena and the Docks.
The city offers too great opportunities to eat and go out.
After two or three days there will be little that you haven't seen in the city. You could choose to make a trip to some town in the region or visit one of the big cities of Spain. Within one hour of the city you can find Sagunto (old roman town with the biggest castle in Europe), Xativa (really nice medieval town) and Teruel (best example of mudejar architecture in Spain). Otherwise you could go to Barcelona or Madrid both around 350 Km away from Valencia.
Enjoy your trip!