And yay, what big decision you have ahead of you. Well, both yay, and as you're experiencing, a bit stressful.
If the two of them came from the same cage at the store initially, you shouldn't have many issues. You still may not have any issues even if they were housed separately at the store. Often the stress of a ride home can help them bond with each other in the car if they're sharing a cage. Also, a new cage at home that is neutral territory will help minimize conflict as well.
Just watch them. The rule is 'no blood no foul'. They can get quite vocal with each other as they work out dominance. Minor scratches are okay on a hairless...they tend to collect them anyway because furred rats don't think to curb their toe nail scratching for those with less fur. Interestingly hairless rats tend to be very gentle with their toenails, esp. if they've been raised with other hairless.
Rats of same genders will get along well with one another once they've gotten to know each other. We can provide all kinds of links to help learn to intro them properly if they just don't get along, and of course we'll be happy to mentor you all along to the best of our limited or not so limited experience.
The biggest risk of getting pet store rats are getting a female/females who are already pregnant. It's very common no matter what they say. Or even having them send you home with a young male and female they /insist/ is two of the same gender but ends up being a breeding couple. Ack! You also may find that because of the stress of coming from a bulk mill breeding situation they'll be more prone to respiratory illnesses. Not always true, but the poor things are definitely not raised in ideal settings to promote health and longevity.
Make sure they're healthy looking and acting, and with a calm gentle temperament before you bring them home. Don't bring them home if they're skittish or don't look or act healthy, even if it means passing up this hairless opportunity.
I'm speaking from personal experience. I love my two hairless, but I've spent literally hundreds of dollars keeping them healthy and so many headaches and money spent dealing with hormonal aggression issues because of their shoddy breeding.
I promise, you'll be happier looking for personality and health first and waiting for the rats who choose you.
Another option is looking on craiglist, freecycle, and petfinder etc.
As for hairless rat special needs. Lessee:
Their temperature runs a little naturally higher than a furred rat, so they need more food/calories per rat than their furry brothers.
Temperature control is even more important to them as well. They should have lots of snuggly hammocks, blankets such to stay warm. I'd even say aside from a rat's natural need for a companion to stay psychologically balanced, they need companions more then others so they can stay warm by snuggling with them.
As I said, they are more prone to scratches and nicks because they lack the hair to protect them. You'll want to keep those clean and be on the lookout for abscesses, which require a vet visit to drain and a round of vet prescribed antibiotics--we'll often call them AB's for short.
They tend to get nastier than furred rats, so I baby wipe mine and condition their skin by rubbing a drop of olive oil all over them every so often.
Health wise, depending on the line they belong to, they can be healthy, or very prone to respiratory or body infections. My personal opinion as a layman, and there are many who will disagree with me, is that hairless rats from pet stores will tend towards less strong immune systems because they're so popular (over bred) and no consideration is given to keeping them healthy.
Some private breeders know how to breed them healthy whether they are true hairless, our some double rex variation or other. If you're interested in the research you can learn the difference between them, but in a nutshell, double rex are more common, more are stronger health-wise, and more apt to be the ones you see in pet stores. They start out with hair as babies and lose their hair as they mature. They still keep some hair on their eyebrows and noses.
I may be missing something, but I'm sure we'll get to all of the answers before too long. LOL
Once again, welcome aboard!