Need to repair and waterseal my concrete deck

I have a concrete deck that is need of some surface repair. There are two layers of thin concrete on top already which I have started to remove (both were already coming up and part of the problem). There are a few issues I am not sure how to deal with since my 9-5 office job has not prepared me for deck repairs. I have added a few pictures to go with my questions below:

1) need to finish removing old concrete and repair the surface/make it level. There are already a few spots I can see where the original concrete slab has small chucks out of it.

2) Need to secure the flashing to the side of the house. Since the deck is not properly sloped to allow the water to drain away from the house, flashing was adding to prevent the water from collecting against the siding. Now that the concrete layers are being removed, I need to make sure the flashing is secure and also need to know what to do to make sure no water gets under the edge of the flashing.

3) The main reason for doing this repair is water is seeping through the concrete into the garage below. I was planning on using the new Rustoleum deck paint once I have the surface redone to seal the top from water, but what would be the best way of finishing the surface before the paint? Do I just patch the surface to fill in the small holes or should I add a new layer of concrete?

Any help on this matter is greatly appreciated. Thanks!

 

Apparently someone already tried to add a new layer of cement. I don't think a new layer will stay. Just patch the original unless you want to brick the entire thing & give it a new surface.

 

If you remove all the old skim coats and give the concrete underneath a good pressure washing you might be successful with a modern concrete resurfacer. I think the flashing is going to be a problem spot so as long as you are removing the old concrete overlayers I would remove the flashing so you can create a good clean area underneath for new sealant to bond.

 

Why not properly prep for and place a thin-bonded concrete overlay? You could use proper pitch to drain all water away from the house, making sure to have at least 1-1/2" of concrete thickness at the low end. The previous layers of concrete were not installed correctly, with lots of indications of improper surface preparation (surface delaminated, too smooth in areas, dirty, etc.).