out of the 4 b18b's in a civic that i hang out with here in town non of them have paid more that 1850 plus shipping they were all bought from personal sellers who ran shops somewhere in the US. only one of them got f*cked but even after he got f*cked the guy he bought it from refunded him for some of the money.
just do your research and i am sure you can find a good deal the main thing is to ask as many ?'s as possible about the motor get as picky as asking if it includes an intermediate shaft a starter an alternator ecu axles map sensor distributor etc. any little piece that can be taken off and sold for money you wanna make sure it comes with the motor if he is saying its a complete swap. and pictures lots and lots of pictures. from every angle front back left right top bottom you can tell alot about a motor just by pictures. oh and you may wanna get the vin of the motor before you but it and run a carfax on it to see milage and see if its stolen or not.