Any advice on logic of a building tool?

I am making a warfare game involving building bases. In order to do this I need to create a tool a bit like the stamper tool that ROBLOX created years ago.

What I've Done So Far:

I've placed the model I want to place inside the CurrentCamera of the LocalPlayer, so that other players don't see what they're building. I then move the CFrame of the PrimaryPart of the model to where the player's mouse is. I would then place it there.

However, this is not satisfactory, and here is what I need to do:

Problems and What I Need to Do Next:

It has some major problems/inadequacies, namely:

1. It is designed to move every time the player moves the mouse, but if a part of the model happens to be in front of the mouse due to camera angle, etc, then it will spiral towards the screen.

2. It also doesnt work exactly how I want it. For example, I can place a wall in the middle of the air, because I just place it based on the CFrame of the mouse. So what do I need to do to make it only placeable on surfaces, e.g terrain, and bricks, etc?

3. Also, due to FE I cannot place it directly from Current Camera into workspace. So I would expect to need to create an Event. But how will the event I fire be able to know the CFrame, and part that I am placing? I.e how can I use variable arguments from the Client to the Server.

Any advice on how to solve the 3 above problems would be great. As a side note, does anyone else think it is silly that Devforums are private? Surely a lot of people would benefit from it without being already established developers?

Edit: Formatting.