The joists were lowered and a thick mortar and later concrete bed was put in, with tile installed on top.

If you are able to save up and land a 2-4 unit property and add some value to it over time while collecting rents and learning how to manage a property, you will be on the right track and you will also learn quickly if you have the thick skin to manage multiple units over time.

Now I understand that you give out your number and email, and agree that is a bit annoying but maybe I'm just thick skinned with that due to my policy of aggressively unsubscribing from email lists. 

Just tell them if they change their mind to give you a call.It's part of ANY business that you will run into people that get angry when they do not get what they are expecting or want to solve a problem.You have to calmly work to see if there is a solution for them after the anger subsides.If there isn't you wish them well.If there is a solution they are open to then try to get the business.If they are open or not ready yet you follow up until they are.It's nothing personal and you have to have thick skin.

You might want to check around a bit on block wall pricing - in my area, a 4" thick 6' tall block wall runs $20-$25 per linear foot , so $6k would cover 300+ feet.

While it's a pain, you can trim studs for the difference in thickness, hammer a chesel and a little skill.Have you considered covering it with a shower surround,flat stock and cut it out for the window ?.....

Grow some extra thick skin.If you are a person of faith, turn to that faith.

He rented a two inch pump with hose and purchased some thick rubber gloves that cost $12.

[i]I don't know about pre or post permitting, but loose soil, whether dumped out of a truck or dug up and loosely spread, will compact about 10-15% (ie. 1.5" per one foot of thickness).

Browse through the books at the Home Depot and pick out a fairly thick, general one and just read it.