I would consider myself an above average swimmer. I've swam quite alot in my life and feel very comfortable in the water. I can easily swim without a life jacket and actually prefer to not wear one. (my friends and family all wear them 100% of the time in water)
I do ok under pressure. I've played sports so I am able to focus in trouble.
Would be willing to put some time into this. It's something I've always wanted to do.
Moose, I agree with Herman, this post cinched it.
First off, diving is not difficult or strenuous. Sure getting in and out of the water means lugging about 75 pounds of gear but after that it's relaxation for the most part. In concept you are trying to be as relaxed and efficient as possible. The general goal is to maximize bottom time while sightseeing. I call it an anaerobic sport.
Diving is an adaptive sport to begin with. I know my mom taught me not to breathe with my face in the water! Every diver has gear preferences and needs. Size is simply one avenue of adaptation. Custom wetsuits and dry-suits are commonly available. The clientele includes folks with needs running the gamut, so you are covered on the exposure protection.
Buoyancy compensators are available in a range of sizes and an experienced shop probably has you covered. If not, a plate and wing system fitted with webbing sized to fit will have you styling!
Neither of these items cost much more than off the rack gear. once you have all of your gear a day of shore diving is the cost of an air fill ~$5 per tank. 2 tanks is usually enough for most divers if the site is handy a single tank outing is even more common. This will all vary with the situation but diving for an equipped diver shore diving is cheap! Vacations and charter boats will drive the cost up.
With your personal gear behind you the cost of the rest is probably between $1500 - $2500. This will vary with new/used (most go new) temperature range you are dressing for and if, what & how many cylinders you choose to own.
$375 for the class and up to $300 for the personal gear sounds about right these days. mask, booties and fins need to fit and the snorkel is required. The
mask in particular needs to be personally fit and IMO is a must own item for anything past a discover dive. If you can try some shop fins in the pool before buying it may help. Your sense of what you like will be new but fins are probably the most expensive and subjective item you will be buying initially.
The discover dive is a splendid opportunity and plan. Given your water skills a good time is almost guaranteed and the hook will be set. The nice thing about doing the DD is that you will start class already KNOWING that you can do this. It should peel away layers of self doubt, concern, anxiety or whatever gets people going downhill.
Have a great time and keep us posted. We we all new to this at one point.
Pete