Rats are good pets but there are a few things to consider, first off, please understand that there will be vet bills.........rats are accident prone
not all the time but the odd one may need to be looked at.
Your cage bar spacing is too wide, go by the rule that rats can squeeze through bar spacing the size of their head (usually complies with kittens). Pref spacing should be around 50mm, adults 1 inch.
Cages I would suggest for a starter is the freddy savic 2, or any rat freddy cage, jenny cage, 'the explorer' or the liberta cage. Below is a handy rat cage calculater, don't go by the max amount, if it says 5 rats, keep 3 etc.
rat cage calculator
Rats need to be in a min. of 2, no reputable breeder will sell you just 1 rat, if you have none, keep that in mind
There are a wide range of cages available online, so have a look about. If you can not afford a cage and your current cage has bar spacing that it too big, you can always place metal netting on the outside but think carefully.
I would not suggest buying rats from petstores, they tend to be rat farmed and are rarely the picture of good health. Basically, you may well be looking at many vet bills and ashorter life span. A good breeder will provide you with papers, you'll know the line and in the safer knowledge that you have a healty rat.
Also, petstore rats are hard work to tame, they haven't been handled since birth and being stuck in a cage, with out taming, will give you a less enjoyable time. Breeder bred rats are more friendly, they are use to humans and not as much hard work. I have experience from both sides, I would never buy a petshop rat again
Research rats, they can't have sawdust or dusty beddings (
pine & Cedar bedding is extremely harmful to rats), it's bad for them and will eventually scar their lungs (
cotton fibre bedding is a no no too). Meaning frequent vet visits and money for antibiotics, you can use eco-card, hemp bedding, carefresh, shredded paper. A lot of decent beddings you can buy from stores that sell horse bedding. Hay isn't really advised, as it can be dusty.
For food, store stuff just doesn't meet the requirements of a rat's diet. You can make your own base dried food, i use;
Red/green/yellow lentils
poppy, sunflower, sesame, linseed,pumpkin seeds
oats - fresh and porridge
green split peas
sweetcorn (the popcorn pod thingys)
Hemp
wheat
crackers -dry and rye
Barley
brown and white rice
white and brown pasta
spelt flakes
maize
soya beans
assorted beans mix
peanuts, walnuts, hazelnuts
dog kibble
You can use cereals, just break them up.
All of the above, i put evenly into a container, mixed it up and last weeks. I add fresh veg to it;
tomatos (vit c)
cucumber
lettuce (don't use iceburg)
carrots
fresh herbs (parsley,mint,thyme)
apple
banana (although this tends to be a dry version)
couple of times a week, they will get a treat, yogurt or baby food, rats love baby food
Add meats in too, dried meal worms are a fav, you can give them cooked meats too but only a little.
Male rats need twice the cleaning routine on a weekly basis, compared to girls. Unneutered bucks do smell, so be warned. Males are lazy and like their cuddles, females are active and like to search.
Keep their cage somewhere that will ensure they are busy, as kittens, they will need the use of ladders but as they get older, give them more ropes etc.
You can make hammocks out of clothes, own materials or buy them but make sure you have spares, as you will need to wash them every few weekrs. Here is a picture of my cage;
I change the lay out each week but you should get the drift with that pic.
I make hammocks out of old tshirts of mine or my sons, along with hammocks i brought online.
You can make 'dig boxes' for your ratties, they love to scavenge and hunt. Pretty easy really, get a big plastic tub (washing basin/toy box etc) and fill it with soil/hay. I use hay as they can be messy, i hid nuts, other bits of dried food (treats like dog chews etc) and they spend ages going through it. Some people use sand but if you do, make sure you have checked that there are no bugs, use play sand. Some people use soil and plant herbs in it, like the below picture;
picture taken from this linked site
When I let my rats out, they get a tub filled with water and peas/sweetcorn at the bottom. I filled the tub up with 2" of water and they go fishing, they love it
within the cage, if you are going to use wood for housing, make sure it's non-treated or treated purely for the purpose of rats. Cardboard boxes make good rat houses, although they will be prone to eventually eat it
empty ice cream boxes are good too.
There are certain illnesses that you have to watch out for with rats, the below link will give you a much needed i-ndepth look;
Rat health guide
Don't be put off by this, it's just for FYI purposes.
I am pretty brain dead at the moment but if i think of anything else, i'll let you know.