Although my situation isn't quite the same, it was similar. I'm in first year university, and started learning the art of pickup when I still lived with my parents.
I'm not sure what your exact problem is. If it's your parents seeing a different girl every saturday morning, well, they should realize that you're an adult and you
can live whatever lifestyle you want.
If the issue is being embarrassed about bringing a girl back to your parents place, I can relate.
Back then, girls my age were in the same situation as me and lived with their parents so they didn't mind, but the thing is, every now and then I would pickup older girls and lie about my age. The house would become a problem. Even when my parents were out of town, it's still way out of a 20-something y/o price range - so it just wasn't believable.
There are a series of things you can do before having to resort to pulling to your parents place.
First - go for a push instead of pull, try to go back to her place. there's a number of ways to do this. Try to inject something about her apartment into early on in the conversation, and keep that topic going for as long as you can. you should get some valuable info that you can use later to your advantage. The more she talks about it, the better the chance that you hear something good. Anything really, such as her desk chair is wobbly, she has a painting by some local artist, she has an instrument you play, etc.
Then when its time to push you can bring up any of these things and say, i took a carpentry class in highschool, i'll take an unlicensed look. joke around about ordering parts from oversees and that you'll be sending her an invoice CASH ONLY.
or you can bring up that local artist, say that you missed the exhibition last month. joke around about stealing it and then turning out its a fake.
or ask about her guitar, what make, 'a fender realllly? she'll ask do you play? and you say\ mann i havn't played on one since i lost mine in a fire last year or whatever. preferably dont lie, that could easly come around and bite you in the ass, but desperate times call for desperate measures.
A car is the next step. If you have a car then you don't have a problem. If no, again, you an figure out if she has one by leading a conversation that way.
If the push isn't possible, go for a walk in a park nearby, its very romantic and is easy to escalte, you can settle for a bj on the bench, Or have some dangerously wild and spontaneous sex behind some bushes. Try do to stand up sex as much as possible here...
Hotels are an option, I used to pretend I'm in town for the weekend. Once a girl called me out on being married. I was fucking 18 at the time. In the end I ended up telling her my age and the reason for the hotel. She didn't seem to mind, I think she was happier with the age thing then a married possibility. Just be aware that the more you seem sketchy about avoiding your place, the more she'll flag the affair card
I don't know if this would apply to you, but I would go to all inclusive resorts with my family now and then, and I would split a room with my siblings. so forget about pulling there at night. I did, however, pull during the day when they're playing in the sand, but girls+alcohol+night= horny, so i eventually built a system of isolating>talking outside>late night snack>walk on the beach>beach lounger sex. It's uncomfortable, but hey, it's better than park sex or no sex. One year, we stayed at a resort with these fancy memory-foam-water-resistant-matress/lounger with moquito nets right on the beach, now that was a nice upgrade. I remember looking at pictures online and knowing i was going to defile that exact one.
so, if you have a beach nearby, drive out and take a walk on the beach
If all of the above is just not possible, then you can blame the economy.
DON'T
unless this is a girl you care about and don't want to lie, by all means do whats right. BUT if this is a club girl one night stand, she would much rather hear something like (as your walking home with her)' Now, brace yourself,, what you are about the hear makes me want to leave right now [playfully push her away] tonight was just supposed to be a guys night out, and to meet YOU of all nights...I'm a little embarrassed to say this, but [create anticipation] I.... am.....gay(a unicorn, a zombie) anything ridiculous, so when you do tell her your actually taking her to your parents house beacuse you're renovating/painting/ converting your den into an amerian gladiators arena, complete with tennis ball guns and steroid monsters in spandex, she won't care as much.