Congrats!! Have you found out more information now - or a midwife that will support you? I'm a mom of twins, but didn't have a VBAC. I have read plenty of stories of twin mom's who have done VBAC, even at home. Check out the book "Having Twins and More" by Elizabeth Noble. I'm sure there are others too - but that book was helpful to me.
I had a home birth with baby #4, then called the midwives back when I was pregnant with #5. I looked big, but didn't measure big until 20 weeks, had a US and TWINS! They were in their own sacks, I was relatively low risk otherwise, and my midwives had delivered several sets of twins before, so my midwives were comfortable continuing with HB, as long as I made it to 37 weeks. They didn't have a Dr. affiliate in my area, so they wanted me to arrange a back-up in case of labor before 37 weeks. However, how do you ask a Dr. 'So, will you be my back-up if something goes WRONG?!' so after several conversations, the ER was my back-up plan - and live in a metro area so there are probably 4 hospitals with-in 5 miles of my home. Their only other criteria for me was to hire a 3rd midwife to help, so that in the even of any issues there would be one MW to attend to each of us.
Definitely seek great nutrition - lots of protein, iron and water. (I did become anemic late in pregnancy - Floradix helped tons) I took naps daily. But never was required to go on bed rest. Every day was chalked up as 'made it one more day!' Until finally at 38 weeks I wondered if they'd ever be born. We made it to 39 weeks 2 days, delivered at home, 2 healthy big girls 50 mins. apart. 7lbs 14oz, 7lbs 9oz. (baby 2 was breech) Everything went so well, we really didn't need 3 midwives, but it was nice reassurance and to have the 3rd as she was an expert on breech babies too. So she mainly got to hold babies and paint toenails so we wouldn't confuse the babies with each other while we got to know them.
I'm actually 15 weeks with baby #7 (DDC December), and am wondering if it could be multiples again - or if my belly is just that stretched out - I look HUGE already. Get to meet with the MW in a few days for the first appt.