hey manda. it all comes down to what YOU can afford. not whats being told to get, (NO OFFENCE ANYONE, but she IS saying shes not got a lot of money and i almost fainted when i saw that animal list) an addictive hobby i went from one to 18 in like three months.
MY SUGGESTION. if you got say a 5 gal you could divided down the road in half and then have two ^.^
but if you cant afford that id scrimp as much as you could to get atleast 2 gal, if your house is heated or one room can stay heated warm enough to keep the tank warm then u wouldnt need the heater.
you dont need to buy 10 different types of food RIGHT AWAY. my bettas lived only on betta bite pellets for like 2 months, but now they get varied diet pellets, flake, frozen brine shripm, frozen blood worms and daphina (frozen and dried)
my fish dont have ornaments my males are in divided custom built tank and a 6 bay and ones in qt, ornaments are not suitable for those tanks but im getting plants to replace the dead moss ive reently removed.
but my lady tanks ALL plants lol and drift wood
plus my bf DISPISES ornaments fake stuff etc