the countertops are
formica or at least the equivalent and I would like to repalace them with
the cheapest solid material that looks good and is the cheapest, granite,
slate ,marble whatever ,anything but corianor similar. most economic
recommendations appreciated.

#2 Granite currently goes for about the same money installed as Corian
and its brethren. You don't have as much color (colour?) choice in
the #2 but the money tradeoff can work magic with your attitude.

I was able to install a granite counter top, with undermount sink as a DIY
project. The BORG did not "allow" DIY instalation but I was able to beat their
price for the material at a local stone cutting yard. Instalation was no
problem except that it required a couple of friends to carefully carry the
counter top from the truck to the kitchen. Also be aware that counter tops (or
other stome sheets) must be transported on edge. I improvised a carrying rack
for this purpose but you might consider delivery.