As I do this for a living I think I am in a good position to offer you some advice. First off you have to treat this as anything you would that involved someone working on your house. That means be sure you have a professional doing the work? What is a professional? Good question.
Here are some things that can clue you in. How long has the person been in business, doing this exact kind of thing? What type of major electronic stores do they do work for? Do they have at least 500,000 worth of liability insurance? In most states a contractor's license is not needed to install small dish units, but it's a good question to ask if they have one? Are they being realistic with whatever estimate they are giving you over the phone. It's impractical to think a 100% accurate estimate can be given over the phone. So they should be asking lots of questions about where it's going, do you have a main junction box, etc etc. If they are not asking a lot of questions and given you a pat flat rate, that's not a good sign. I wouldn't worry about him having to rent a ladder necessarily. Most installers are not going to have an 18,24,32 foot ladders. They just aren't used enough to be worth having. However they should have a normal 8 or 10 ft ladder no doubt, and following that logic they should have plenty of tools. Tone generator, signal meter, proper mounting tools for all materials, etc etc. They should have all the necessary accessories you might need. Such as diplexers, multi-switchers, coax, tips, etc. Finally, and maybe most importantly, they should not only install it and get a signal. They should finish hooking it up complete to the tv. They should wait with you as you call DirecTV or dish and activate the system. They should show you quickly, how to use your given equipment brand. This last step is something that takes an extra 10-20 min and is rarely done by someone who isn't professional.
Finally remember this fact. Just like having any work done on your house, most of the time you get what you pay for. The professionals have licenses, insurance, tools, expertise, schooling, etc to pay for. So don't expect to get a good job done for a cut-rate price. End the end I REDO more installs then I get fresh ones. The customer ends up having to pay twice. Don't do something like that. Get it done right the first time.
Hope this helped.