In the cruise LOP you can save a bit on the 23 gallons in my IV.
I budget on 310 per hour @ 200 hrs p year and it seems to do well but that all depends on how you treat the engines....
I had a JPI installed with gami injectors to treat the babies well (temp checks on all cylinders). These engines are notorious for not dealing well with shock cooling.
The heater is a bit sensitive and needs good care.
All the V's have the new waterbased paints and so I see a lot of V's who look worse than my IV, but then I still run on steam gauges and many V's have glass panels if you want that. Hangerage will conserve your paint a lot.
There are excellent buys at the moment for Seneca II, IV and V .
Most are at 1999 kgs and save you a lot of money (it s paperwork only, no mod to the aircraft). I think it would be foolish to fly a 2000+ Seneca