I have a Cessna 172. There are two scenarios for choosing an FBO.
First, if the choice of an FBO in the neighborhood within 200 miles of my home base is usually determined by the price of fuel and the proximity to food or a destination. For example, when I was based in New England, two airports were usually on every pilot's go-to list: Barnes (KBAF) and Sky Acres (44N). Both had very good fuel prices and an on-field restaurant. The one in the terminal at Barnes was a little fancier and pricier than the one at Sky Acres, which was closed during most weekdays. Fuel at Sky Acres was self-serve and the fuel at Barnes was delivered by a tank truck. Both sported friendly people, although Sky Acres did not have any line staff. Whenever we went on a cross-country jaunt, we'd stop at one of these fields to refuel before going home for our last leg of the journey. Sometimes they were the destination themselves, just for the meal.
Sky Acres had one old sofa near an old stove, but very few people bothered to sit there. There wasn't a convenient place to do flight planning and getting a briefing was up to you and the drafty phone booth outside in the cold. Barnes, being a terminal, didn't have very inviting pilot services either.
In earlier days, another destination of the same sort was Columbia County (1B1) in New York near the upper Hudson River. It had no services except cheap self-serve fuel and a good restaurant within walking distance. But, we stopped going there after the restaurant burned down. Food is very important.
The second scenario for choosing an FBO is determined by quick, inexpensive, and easy in and out. It includes the price of fuel and proximity to food, but it also includes easy access to overnight accommodations and up-to-date flight planning facilities. These are the stops for a real cross country multi-leg journey of 600 to 3000 miles in length. Here are the criteria/steps we go through to plan stops along the way:
We consider airports within 50 miles of projected route of flight or possible deviation toward the destination. For example, if we are flying from New York to Oklahoma and there is a line of thunderstorms expected to rise from the Gulf to the Great Lakes, we might also consider airports all along the eastern seaboard down to Georgia as well as straight westward routes. We plan to land every 3 hours, which is usually every 300 miles. As an FBO operator, there is nothing you can do about this first consideration.
Next, we get the price of fuel from 100LL.com and AirNav. We eliminate the most expensive stops. We eliminate all stops that are more than $1.00 more in price than surrounding stops. Preference is given for inexpensive self-service fuel.
A good weather/pilot planning facility is a must. We need to be aware of and on top of the weather at every stop and we need to do it quickly. I need an Internet connection, free wifi for my tablet is good, too.
These stops will require quick food and water as well as available transportation. So, a crew car scores high, but food and inexpensive lodging within walking distance will suffice. We need to be able to spend the night if we get too tired to continue or if we experience a weather or mechanical delay.
A mechanic's facility on-field is another consideration. We don't expect to break down, but you never know and we have found ourselves stranded for days at a time waiting for a repair.
I don't care about your furnishings. If your facility is spotless chrome and glass, that is OK. If it is warm and cozy, that is OK, too. I don't have to live there. But, please make sure the bathroom is clean.
But, let me emphasize that being greeted with poor service or a surly attitude will forever put your FBO on our -Always Avoid- list. If we have to wait around, don't expect to see us again. If you don't provide restroom facilities that are available 24/7, we won't come back. Although we have a cell phone, we also need to be able to use your phone, because ours may not be able to call out. If we ever land after hours and feel stranded, we'll never come there again. If we feel we've been gouged, we'll avoid returning. I don't like ramp fees.