Built a few of those, The decking can be the most expensive part. But with 2 guys and sweat equity you could be under 2 grand. You say Porch and deck interchangeably. Is it on the ground or is it a first or second story Porch? Guessing porch since you mention stairs.. I always set my floor joists on top of an outer married bean support. Alway Lag the ledger to the home structureI just got a price to build a 10 x 12 ft deck on the back of my house in New Jersey. The price quoted for removal and disposal of the old porch, a set of stairs and a cement pad, permits, and installation of the new deck with new footings was about $10,000. It seems like alot of money for some wood and hardware. Being the deck is relativity small, I decided were don't need one that bad.,,,
If you can't burn the old lumber in the your back yard, dump runs with construction debris can be $$$.
Got any buddies with some carpentry in their blood?