I agree with librarychick. I've actually been in and am still in your exact boat (rescuing "feral" kittens and finding them homes). Your guys aren't feral now, so I'd stay way from that F word.
The goal is to make everything a positive...even things that aren't. Instead of saying "they had worms and fleas" play up the fact that they've been checked by a vet. I hear you on the details for used/vintage ebay items, I've sold items that way too. The difference here though is that people can "see before they buy." You don't have to describe every little flaw. They can see whatever they would like to for themselves. And "flaws" aren't permanent in cats they way they are in objects. Did it have fleas? Sure. Does it now? Nope. The fact that it had fleas is mitigated by the treatment you gave them.
Here's the exact text of the ad I used for my last batch from a mom who was feral when she came to me (sorry, I'd just link the ad but it's long since expired).
Kittens want a home for the holidays--ALREADY FIXED (Lacey, WA)
I have two kittens left from the same litter who are in search of great homes. Two males. They are approximately 14 weeks old. They HAVE already been spayed/neutered and are healed up from their surgeries and wormed and treated for fleas. They have not had any shots. Both are short haired. I have put a lot into these guys and want to keep track of them, so please live within 20-30 minutes of Lacey (near Olympia, WA). I won't send the kittens to homes further away than that.
This litter was born in a shed in Rochester and spent the first 3-4 weeks of their lives there. They were brought to me with their mother about 10 weeks ago. I supplemented them with kitten formula for the first two weeks until they got the hang of eating on their own. They are all sweet kittens and learning how to be good house cats. They have been indoors only for the last 8 weeks. They have been using the litter box without fail for the last 6 weeks. They have been introduced to the other adult cats in the home (of varying age, sex and temperament) and managed to get along peacefully with them. They also don't seem to care one way or the other about our dog (lab mix) except that they think her wagging tail is a great toy.
They will be going to a home on an adoption contract stating that if you cannot keep them for any reason, they must be returned to me. I do plan to do some follow up calls/emails to make sure that the adoption is working out well for everyone. I had these kittens for the last 10 weeks and invested a lot of love and energy into them. I want to make absolutely sure that they are in a great situation. Adoption fee is $75 each, which helps to cover the cost of their surgeries, medicines and food/litter. I am going to screen potential homes and will not let them go to a home that is unsuited. For example: if you rent and plan on hiding the kittens from your landlord, please do not respond. If you plan on getting a kitten as a gift for someone else, please do not respond. If you are under 18 years old, please do not respond. If you are not planning on keeping the kittens for the duration of their lives (approximately 15 years), please do not respond. If you plan on making the kittens outdoor only, please do not respond.
I usually foster for the shelter (this batch is not from there) and have spent the last 2 years fostering over 70 cats and kittens. My babies have been exposed to other cats and our dog (a small, mellow black lab mix). Their spay/neuter surgeries were done on November 8th and they are all healed up and ready to go.
*Ivan (the Terrible): Solid black male except for a small white spot on his chest. Beautiful yellow/brown eyes. Ivan is **** on wheels and a classic rowdy kitten, but does know how to snuggle.
*Igor: Beautiful black male with a white spot on his chest and white hair inside his ears. Lovely yellow/brown eyes. He had an umbilical hernia when he first arrived, but it closed on its own and by the time he was neutered, the vet said it had completely healed and so did not need any kind of medical intervention. He is a big snuggler and has the best purr of the bunch.
****Picture of them in the blue cube shows the entire litter of 6. Any not listed above have already been adopted.****
Please respond telling me what kind of home you can offer a kitten(s) and which one(s) you are interested in and I can write back and arrange a time to meet you if it seems like a good fit. I am available for the remainder of the weekend.