Suit cost is directly in proportion to the amount of exposure protection it provides.
A 3mm wetsuit is cheap. A 3mm shorty, even less expensive. At $10 a day for renting a suit, you can pay for one very quickly. You get the comfort of a suit that fits, and one that you can take care of so it does not stink!
THIS is the wetsuit I have, and at $120, it's superstreach, comfortable, and hard to beat the price.
Drysuits are expensive. You can spend $3000 on a high end drysuit. Most don't as there are good trilams available for under $1500. That still is a lot of $$$. If you decide to dive dry, you may need a whole flock of threads to research that decision!
You can do the Lakes in a 7mm as some have commented. However diving wet is not as much about time in the water as time out of the water. I did not often get cold diving a 7mm wet while diving, but I froze during SI's. Standing around in a wet 7mm suit in 35F degree weather is not fun. Once you get cold, then when you get in again, you get really cold.
You can remove the suit between dives, but after you climb into and out of a 7mm than you may begin to understand why a lot of folks just leave them on.