$200 + u can easily get a wet/dry vaccum. I not sure what brand is good.. I got mine from courts, i uses it for ard 3 yrs already. I uses it everyday for my job, aircon cleaning =)
You can advise your neighbour to install a alluminium tray below the condenser. So all the water will landed on the tray and flow to their toliet.
I have a aircon contractor, I will pm you his number