Although you chose a painful path to get there I think you look like you are finally headed in the right direction. Personally I would feel bad keeping feeder fish in a ten gallon. Ive never even owned one. The 88 gal sounds like a good plan but make sure to do your homework this time. You MUST know the nitrogen cycle upside down and backwards and you MUST complete it before adding ONE fish at a time. That is if you want to provide livable conditions for these wonderful fish. Another rule with Oscars is mega filtration. Run double if not more the recommended filtration. Realize that even if the tank is cheap you still need:
Heaters
Substrate
Power Filters
Replacement filters
Gravel Vac
Deco
*Stand
*Canopy
*Lights
Thermometer
Food (buy in bulk for that Oscar)
Test Kit
QT Tank fully set up (recommended)
Meds
Nets
Buckets (good quality buckets are a god send but generally arnt free)
And so many more little and large items that you could not even imagine
* = May come with tank
And one last thing, the "biggest (cheapest) tank" is not the tank you will want when your replacing everything in your living room.