Tank dimensions?, plenty of tanks are all shapes and sizes nowadays and the footprint would be all that matters.
What temperature is the tank been or will be kept at?, some of the plecs listed above prefer much higher temperatures than others.
The L260 and the L270 seem to be very hard to obtain at a sub adult/adult size so even though they would be a nice addition they will pose a problem to get larger specimens.
i tend to forget not all counties stock the same fish, luckily there are availible to me
Pitbulls are one of them plecs that do like a few of there own kind so i would recommend a minimum of 3 would be sufficient.
i agree, forgot to mention this
Just remember the plecs actually listed above require very different dietary requirements to each other and you will need to research which foods are best for keeping them.
i was merely giving some examples of nice plecs that are not too large and among some of the '' most pleasant '' the most beautiful in my opinion would be the zebra plecostomus what ever his/her decision, im sure researching that particular pleco would have been imminent