Check Lowes also. They will sometimes have these on clearance, so you can get even more for cheaper.

As for winter care, you have it down, so just prepare that way for the coming winter months.

If you have several and want to leave some outside as an experiment to see what it can and can't handle, you can try to mulch it for added protection.

Ed, I hope your mandevillas are doing well. Get them through the summer before you worry about overwintering. The first one I had didn't survive until autumn. Did you check the Sun Parasol web site yet? They want gardeners to be happy with their plants and go buy more, so there's plenty of information there.

The sites I've looked at disagree on how cold-hardy mandevillas are, but unless you live in zone 8 or warmer, I would not expect outdoor winter survival even with a truckload of mulch.

I currently have three of the Sun Parasol mandevillas, all of which I overwintered indoors last year. All were Lowes clearance buys. Overwintering was not difficult, but it was messy and buggy. Lots of dropped leaves and aphids. I'm not sure it was worth the trouble. There are no flower buds yet and it's almost July. I could have bought new ones in bloom in May.

I'm almost sure the showy hybrids are only zn 9 hardy. As Edie said, they can be hard even to get through the summer!

OTOH Mandevilla laxa is at least zn 8 hardy, but for me needed to stay fairly dry in winter.

I over wintered mine in a cool room on the floor with no sun. I just cut mine off and watered it just a little, maybe once a month. In the spring it started growing again, then I forgot to keep it watered and it died. Darn. I do that with my geraniums also.

I have overwintered mandevilla several times, but 've had very poor luck getting a bloom out of them the second year. They may survive a 2nd winter but usually die the following spring for me.

Keeping them is not hard, in a coolish room (60s), south window, water every 6-7 days. I cut them back also. I've not had problems with bugs.