where should I send my customers to write reviews?

There are pros and cons... stay clear from yelp. Angieslist though would be okay since you do remodeling but you'll have some headaches there, not as much as there are with yelp though. It also depends on your local area, some areas heavily favor yelp and others don't care much. If you're in califonia, yelp matters unless you're upstate. If you're in New York, yelp doesn't matter as much.

For me, I wanted a way to send people somewhere without them having to register. Then I had a bunch of trolls leaving fake reviews too because it was easy.

Thumbtack, insiderpages, superpages, are great without the filter. Thumbtack started using a filter in the past 2 months I think but it isn't nearly as bad as yelp. Google + local for obvious reasons, but then again, you arent going to get many reviews for non google + users.

You can get on reviewopedia but beware, it DOES rank high naturally but the owner chooses which reviews get posted so if you have some negative ones, he will allow only the negatives to show. He will also ban the IP of the positive ones... its shady.

You could also start your own review site. What I do for clients, the well paying ones at least, is create their own business name + reviews.com but ALSO their own city+occupation review site.

All in all... I would stay away from Yelp, maybe have a few good reviews up there but if your customers aren't already active yelp users the review likely won't stick unless it isn't positive. I don't think you should avoid it entirely, but I would recommend spreading the reviews out, and then work on getting the properties up that you want ranking. Next, if yelp stays up there, which it usually likes to stay in the top 2-5 spots, then you should work on getting additional reviews.

It all really depends on how you want to sculpt it. Also, your online reputation is only about 30% reviews, make sure you rank your other properties. I like having clients control their top 10 without any review sites, but then still working on positive reviews so they can link potential clients or have a link on their website. Most though, we get their top 10 looking like this:

Main website
Website + reviews.com
Website name.net
Facebook
Twitter
LinkedIn
Youtube
Press Release
Article (squidoo or hubpages usually)
YouTube Video

2nd page will usually be mostly reviews. You never know when someone can run a smear campaign, or when things can go wrong.

Thats why I get paid the big bucks lol.

Nameless gave great advice. To add a bit to this the best advice I can give is the most simple.

You should send people to review you in the places where you expect prospects to find you.

Angie's list working for you? Then you need reviews there.
Google?
etc etc

It sounds simple but it's so important. For us all that really mattered was the google reviews as that is where all our customers look.