I got introduced to the LC470 Lister very recently. That is one badass car. I added it to my must have list. I have driven the beck 550. It's nice but I prefer the 550 made by thunder ranch. Next year I want to pull the trigger on a car that is just completely off the wall and only for fun. But I am poor so really want to keep it under 100 grand. 550 and the Lister are at the top of the list right now. If you want a base model 550 you can get plenty for 20-30 grand. Custom cars with all the bells and whistles and the price jumps real fast. The thunder ranch 550 with the 911 rs motor and 915 gearbox and the race suspension and brakes will set you back around 75k.
http://www.thunderranch.com/550.html The lister LC470 will set you back around 85k-not a beck but same moldings I understand. I am not familiar with the beck lister
http://www.lc470.com/price.htm My other car I am interested in buying is a d-type replica. Problem is this will take a few years to build and may untimately not be legal in the US.

Finally if this year goes really really well I would like to get a GT40 with a rousch 427. That thing will set you back about 130 grand. Doubt I will do so well in the next 11 months. Driving the 550 by beck is alot of fun. It's kinda hard to say it's gonna drive a certain way. I have yet to see 2 of them built the same way. Some have great suspension setups and others are just lookers with buggy engine, suspensions and transmissiions. The one I drove was pretty nice but with only 125 hp type 4 and made for cruising. It will get you going in a 550 since they weigh under 1300 lbs. The swing axle is not a very good design, you can make it work but better to step up to something more like the later rsk suspension. Most 550 builders have that as an option. The transmissions can be anywhere from bad to worse. Unless you are willling to accept that old cars just don't shift as well as new ones you would probably be disapointed. Also no power steering or power brakes. If you just want a cruiser then look every few weeks on ebay for a type 4 550. If you have an exact image in your head of the perfect 550 then I would talk with the guys at thunder ranch first. I'll stop now I can ramble on about old cars for far to long.