Grout Perfect makes a good color seal product.
Sales kit is a must. I've closed just about every time I've done a demo, including two $1K jobs yesterday. Even when I didn't close a deal it was because of price. The person was still wowed by the demo.
The roller pad is also a must.
I didn't order the Starter Kit because I didn't want to get stuck with a bunch of color seal that will never be used. GP states the colors are the 12 most popular - or something like that - but I've ordered only a few of them. The same colors are in the sales kit. I would not order a lot of stock, or any really, until you get the jobs lined up. I order as I need it.
Also not crazy about the shammies they provide. I'm glad a couple of alternatives were mentioned.
The down side to GP is the ordering. Even though it's B-2B, you can't established an account with net terms. From what I can tell, they use a middle-man shipper which adds at least a day to the shipping. You can't get a firm arrival day on shipments unless you pay extra for 3-day air. This really screwed me on a big job once even though the person who took the order called back the same day and confirmed the arrival date. She called back the following day and said the shipment would arrive two days later; after I had already scheduled the job within the narrow window available for the client. I won't tell you what I think of the woman in the office with whom you place an order. This is the reason I'm trying out product from This Old Grout.
Again, a good product.