Use pressure treated lumber for the subframe and price out different decking materials, wood vs composite and the different railing kits.

There are so many utube videos on all aspects of deck building but it will depend on your own confidence and ability to use tools safely.

the whole wall ranges from 1/2 to 1+" gap. would need lots of caulk

https://imgur.com/a/W2xzyTF

If it flushes itself, it's overfilling. Either your fill-valve is faulty, or incorrectly set. There isn't any other reason. I'm a trade plumber, trust me. Some images would help. If your flush-syphon is a telescopic one, this could also be adjusted incorrectly. Post some pics, we'll get you sorted 💪

Are you sure your float stop is adjusted properly? Water should stop before it reaches the overflow.

could be your flapper is too light ( or uneven / dirty like the other person said). put a small weight like plasticine / sticky putty / glue a washer on it. might help.

Saw someone else mention some kind of membrane. Not familiar with that although I have seen Mike Holmes use an orange material that gets thinset to the floor then the tile laid on that.

I would make sure you clean around where the flapper sits. Make sure you have the correct parts for that toilet. Sometimes the universal crap can cause problems. Go to a plumbing supply for parts.

This answer told me so much I didn't know. Thank you!

It has a white plastic strip embedded in it. The irregularities come from Thinset that was used to fill the crack a long time ago it seems.

For myself a deck on someone elses cement work? A piece of cake and a fun weekend project. On the other hand I have a brother in law that couldnt nail two pieces of wood together to save his life. You likely fall somewhere between. Have fun, take your time and do good work. It will probably take longer than you expect but it isnt a race.

See if you can stuff some insulation in first than the backer rod. Do you know if there is insulation in the walls??

Very easy for some. Very difficult for others. All depends on the person

Looks more like a settlement crack. I would expect to see a perfectly straight line and expansion joint material in the joint. Too many irregularities in the crack to be made on purpose.

You may find the tile will also crack over time if the slab continues to shift.

Go to Taunton.com and buy one of their deck building books.

Go to your permitting authority and ask for their guidelines and code requirements for building decks.

Easy but manual labor

I would use caulk.

Home Depot and or Lowes have diy books covering the planning and construction.

[removed]

Pretty straight forward if you plan it out.

Take your sweet time leveling the joists and on the stairs.

Backer rod and Big Stretch caulk.

Ohhh the color of the wood really pops against the desaturated brick exterior. Lovely work.

Thank you. I really appreciate this. I’m just really hoping it’s safe for now.

I have complete faith in you.

Read the whole, his balls get stuck bit and was having a hard time figuring out how. Lol

Edit: Also, nice job

This. Replacing a switch that shoots sparks and turns off a breaker that controls power to the entire upstairs? Easy! Figuring out why that switch turns off a breaker to the entire upstairs and figuring out why one breaker controls the entire upstairs in the first place? That's what a paid electrician is for. At least it doesn't shoot sparks out anymore...