I prefer top loading with a coil or even a combo of that and a T top hat or inverted L configuration, inductor at the 90 degree bend. Only drawback is the added top weight and the coil being much higher inductance compared to having it near the bottom tuning section when using a shortened antenna. Also getting the inductor turns right can be a pain since you have to take down and put up the contraption until it's tuned. This can be used as a single vertical antenna this way without needing to tie off wires at the top to a structure if desired.
When I've tried this I notice a considerable improvement with broadcast coverage compared to bottom loading. Has something to do with current distribution in the antenna but haven't had my coffee yet.
As Charlie_Dont_Surf recommended though your standard shortened T antenna (or capacity hat) just "works" and is even used down in the longwave band where shortened antennas are a must.
Of course getting as many radials down is the other functional section of the antenna and is equally important. Bare minimal tie to any large metal items earthed and experiment with that if you don't have the space or wire to put down over the ground.
It still amazes me how much people can pinch out of those pea shooter part 15 setups too. You'd think at some point there would be diminishing results but I guess sometimes every little thing in the overall antenna system does add up 
I designed and built a MW aerial many years ago that was 2 vertical wires, about 20 inches apart, held up by 3 sets of 2 top wires, also 20 ins apart, which went to 2 trees and the house chimney. It was only about 35 or 40 feet high. It worked quite well on 846 kHz (I'm in Europe). I moved the coil to the top and a friend a couple of miles away noticed an increase in signal strength.
Using 2 wires on the vertical increased the bandwidth of the aerial considerably which made tuning much easier and also was important as I was running wide audio bandwidth. Optimod 9100 with filters defeated.
Dropping the aerial to fine tune it was a PITA so I decided to add a little extra coil at the base and fine tune it there.
I have no idea what the base impedance was, or even what impedance the TX was seeing, but as it was a home built valve TX (about 400 watts) I just tuned the TX to match the aerial.
I wish i had pics of it now but it before the days of cheap cameras and phones
I moved house 18 years ago and brought the top coil with me. It was wound on a catering mayonnaise tub
I still have it. The guy who bought my old house developed the site and built 2 new houses on it. I wonder what he thought of all the buried wires were for?
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