Agreed, there isn't enough info.
Bumper fillers aren't a deal breaker by any means. All of the originals tend to go brittle and fall apart. Paint on the cars are notoriously bad, again not a deal breaker if the car is mechanically sound, but be advise it is seriously, seriously, expensive to repaint a car unless you have a relative in the trade. 8-10k (which sounds like the entire price of the car you are looking at) to get a decent paint job. (Which could take a whole year to complete BTW unless you have the a fore mentioned hook up in the trade). It may feel kewl to own this GN, but can your ego withstand 'Car woudl be great if it weren;t for the paint!" comments you could hear? H
The BIG warning flag for me with the little information you provided is 'aftermarket turbo'. There are two reasons for an aftermarket turbo. The first is that the stock went bad, or blew up. The second is a previous owner wanted to go FASTER.
If the stock turbo failed, that raises a whole mess of questions about the current maintenance condition of the car and it's history of repairs.
If the turbo was added to go faster, it simply cannot be the ONLY modification done to the car unless the person was either reckless or a novice. There are stickies on this site that talk about things to do to maintain the car to get it ready to go faster than stock. There are lots of discussions about recipes to make the car go faster. I promise you NONE of them START with upgrading the turbocharger.
If you can get some shots under the hood and the interior, lots of folks here can spot other modifications that may look 'stock' appearing.
We want to help you. The more of these cars that are on the road running smooth, the happier we all are. We never like to see these cars rotting away or blown up. We would much rather see them at our cruise nights and buick shows.
So that being said, I offer the following information not to shatter your dream, but to try and offer wisdom. I say all of this in the spirit of community and hope it will stoke the fires of your dream and not discourage you.
If you search this site there are lots stories about hearts being broken by buying the wrong car. These Turbo Buicks are a lot of fun when they are running and dialed in. They are money pits if you don't know what you are getting in to. You absolutely NEED to know what you are getting into. Many times the current owner just 'doesn't know'. They aren't dishonest, they just never paid attention and cant answer your questions. That is getting a guy who KNOWS specifically these cars is helpful to have when viewing a car. They aren't gonna snipe you, as I said they want you to be at shows with them. Many times if you have someone in your area, they will do it for free or maybe treating them to dinner or something.
IMPORTANT: If you are about to say there isn't a solid resource in your area who you could ask to inspect the car with you, I say: Who are you going to take the car to to get fixed when things break on the car? Many professional mechanics who work on old chevy's or brand new corvettes have been humbled and made expensive mistakes with these cars. Ask your regular mechanic if they have ever troubleshot a GM Powermaster Brake system from the early 80s. They will either laugh or cry. If they don't cry, they don't know these cars. (I am being humorous). If you are planning on repairing the car yourself, quite often you end up throwing money at parts in an effort to 'guess' what might be the problem. How many wrong guesses do you have resources for before you realize you could have put that money toward a better quality car.
With the information you provided, and the pics, you should NOT be talking about making an offer on this car. Not even for giggles. We all understand how tempting it is, especially when there is one near you. Look at some of the cars for sale on this board or even on eBay and look at the details they offer about the car. Look at the pics they give. Lots of the info could be greek to you, but it gives you an idea of how much information you are missing. It will also give you an idea of the pricing in the market. Generally speaking if you find cars with 120k+ and they are at asking prices of 15k, but this owner can get past 8k for his. Look at what end of the spectrum you are falling in for that price range. You are either stealing the car, or about to step in quicksand, filled with landmines, surrounded by starving veloci-raptors, and a hyperagressive land shark. Given the lack of details, you can understand which way the community might think the car is.
The key is to buy the nicest quality car you can afford. I am not saying the 30k cars are worth overpaying for, but look at the market. What is the 15k guy offering that the 12k guy isnt. The 12k guy talks about the new turbo with only 100 miles on it, while the 15k guy listed every component of the car including it's astrological sign and favorite foods.
Please, be patient when you are considering a purchase like this. It can seriously ruin your dream if you aren't prepared. While it may be rare to have one for sale so close to you, these cars are for sale all the time. Identify your goals for your car, and what you plan to do with it. don't let the price dictate your goals. Find cars that match what you are looking for, then compare the details. look at enough of these cars online, and you can almost smell the true lemons.
Post back with more info on the car, and pick of the engine and interior. We all can give you lots of questions to ask the owner.
Good Luck in your search. I hope you get to realize your dream one day. IMO nothing drive like a Turbo Buick.
. In all seriousness, good luck in your search and as others have said, take your time. I have always found the "hunt" to be nearly as fun as actual ownership 
