You can run a dipole between two houses, just be sure to do your RF exposure calculations and don't be surprised if you pick up a lot of RFI. You will need to use insulators between the antenna wire and the supporting rope. There is a lot of voltage on the ends of the dipole. If the dipole is less than 1/4 wavelength off the ground, most of the signal will go up. That's good for NVIS on the lower bands, but bad for DX.
You can put multiple dipoles on the same cable, it's called a fan dipole. The wires have to be spread out and can be a pain to work with, but you can get an antenna that's resonant on multiple bands.