Hello, I need some advice and opinions please.

The car looks like it's in a car yard - you would be much better off both financially and in terms of the integrity of the car if you bought privately from an owner. Car yards have their margins on top and they'll tell you anything to get a sale.
Keep looking as there are nice cars out there. The Barracuda should have a nice vinyl interior, not a furry velour interior like that one. Check everywhere for rust. These cars are 50+ years old. Check the cowl as drains can block with debris, mouse nests etc. Check around the back window. Check floor pans, especially in footwells as blocked cowl drains or leaking wiper seals let water in and soak the carpet.
All the engines and transmissions are reliable with no inherent faults.
The 7.25 rear end is not that strong but mine survived fine behind my 318. The larger diffs are strong though e.g. 8.75".
4 spd cars will be worth more than autos, console autos worth more than column shift. Fastbacks are probably more desirable than notchbacks.
The 340 engine is the pick of the small blocks, but a 383 big block is attractive too. There was a 440 factory option in 1969 but they are big dollars. 318's are reliable and can be made to boogie with a few easy mods.
I had a '69 318 fastback, column shift similar to the photo below. Loved that car, should never have sold it. Good luck in your quest.
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