Marcinde, you're entitled to your beliefs and opinions and I guess this is one of those places where we'll, respectfully, disagree. While most drainage problems require the OP to provide additional information, some of it can be collected simply, with very inexpensive, basic tools if the OP is willing to do it. Most of them are not dopes and can understand the basics, once it's explained. While not everything about drainage can be figured out in a forum, most of the basic issues can ... or be explained so that the OP knows where to go next. On top of that, I think it's a stretch to presume that one has great liability by providing free information that has no guarantee. All of the advice that comes here (and on any forum) requires the recipient to weigh it against common sense. If they're helped, they're helped. If they're not, they're not. And getting advice here does not imply or guarantee that local advice is unnecessary. "...I am very aware of that I cannot just redirect water into my neighbour's yard lest I create issues with (at the least) angry neighbours or (at the worst) potential fines and costly liabilities." To clarify, it is perfectly okay to maintain the natural sheet flow of water from one yard to the next. In fact, it would be impractical to alter it in most cases and impossible to stop it in many. It's a "given" that water leaving one's yard will run downhill to the next lower property. By the same token, one must be prepared to accept the natural sheet flow of water that comes from the next door neighbor who is uphill. Yards are supposed to be graded so as to move water on its way to the next lower property and to the right-of-way, without causing damage. What one can't do is CONCENTRATE water and direct it onto a downhill neighbor's property ... or dam it up so that it cannot leave the uphill neighbor's property. If one has a problem with water being retained in a low area, it's important to know how the grading is configured. It would be nice if it would show up in a photo, but most times it won't. Therefore, one must collect grade information that is measured, not just guessed at. Another key element of solving the problem is knowing how the water will find its way off of the property ... the path it will take. This also requires knowledge about how grades are configured OFF of the property because the question extends beyond "how will the water get out?" to "where will it go?"

You may as well leave the St Aug under the trees since it did well. The rest you can convert to bermuda. It will blend at the edge of the shady areas. Both will try to invade the other, so I hope your not a stickler for perfection. You can seed bermuda. Wait until late May to get started. Bermuda seed needs hot soil to germinate. TexasWeed will be along to help you pick a seed. You'll probably want to rent a verticutter (also known as a power rake, slit seeder, or ). They have vertically cutting blades that can be lowered to below the soil level. I'd take it to the soil level. Rip through everything and blow it into a compost pile. Then seed and roll it down. Water it 3x per day, every day, for 2-3 weeks until you think you have 80% germination. A month later you'll have a bermuda lawn. But wait until late May to even think about it. I know all you can find in the stores right now is bermuda seed, but it is waaaay to early. Zoysia needs as much water as St Aug to look good. If you let it languish, it will go dormant on you and only come back the following spring. Bermuda, on the other hand, will spring back at the first hint of rain or fog. Find the Bermuda Bible on the Internet. Read and heed.

Welcome to the joys of building a pond. I have the Savio compact skimmer (because of it's size). I used a 2" bulkhead fitting in the bottom of the skimmer in that space between the filters and the back of the skimmer. I use a small threaded filter in this bulkhead fitting in the skimmer--just in case small fish came through the skimmer I don't want them in the pump. From the bulkhead I have a short piece about 3" of ABS, then a 90 to bring the pipe up again before going into the pump house. My skimmer and pipework is only about 18" away from the pump. 2" ball valve then a wye as joins the line from my sc. My valves are Ipex valves (given to me by a friend) so have quick disconnects for the pump. I glued the fitting that comes with the skimmer for a submersible pump into the skimmer. The one problem I have with my new pump is that I can no longer run skimmer only when shutting down the sc for water changes. The skimmer draws down too much and the pump wasn't getting enough water. So that might have to be something you calculate for in sizing your pump. In my case I would have to be drawing water from another source-perhaps a midline point but don't have space for any more prefilters before the pump. I also don't have my bd plumbed into the skimmer--someone else will have to advise you on this and draw down issues. If you do a search on this site there are instructions for installing the Tetra bd. If you rock the bottom of your pond there really isn't much point in the bd as it just won't work. The knife valve is to shut off the flow to the pump and or sc for maintenance. Ball valves are usually used to control the flow of the water. Leaf trap/priming pot even if external pump is in ground is a good idea. I didn't have one and found out the hard way when filter floss got wrapped around the pump. If I had a leaf basket it would have got caught in there. Also the Savio waterfall filters are expensive. A skippy type filter would give you more filtration at about 1/3rd the cost.

"The large deck ... is structurally sound, the boards are not in good shape." What exactly does "not in good shape" mean? ... that the surface is not good but otherwise they are OK ...? That sounds like a couple of decks that came with a house I once owned. They were functional but ugly from years of weathering and no attention whatsoever. They were transformed into completely acceptable, nice actually, merely with pressure washing, a quick, coarse sanding, and two or three coats of deck paint (not stain) applied with a paint roller. It was not a huge, horrible job and they looked almost as good as new. They were much easier to keep clean with a hard paint surface. The cost to fix it this way, if DIY, would be a couple hundred bucks. If not DIY, a few hundred ... vs. $17K. If you could get another dozen years our of your deck and have it look nice, too, would that be acceptable? Landscaping is a discipline where one must not ignore site conditions or impose unrealistic solutions if they expect to produce a result that is pleasant, lasting and maintainable. I question the overall direction of making a small porch with steps down to where all the landscape features would be. This seems intrinsically less useful than would be having a decent sized deck immediately off of the main living space. I see a grill but not a dining table. Where does the outdoor dining happen? If the kitchen is separated from outdoor dining by a full flight of steps, it will surely be made much more inconvenient. But the real deal-breaker for me is the imposition of "no groundcover," which is driven by unrealistic beliefs based on emotion, when the site itself is demanding groundcover for practical reasons: there is slope and there is shade. Are we really going to spend $50K in order to change this into flat, sunny ground? It's going to require significant retaining walls & grading in addition to all the other new hardscape and planting. On the subject of husband's allergies to pine, I presume you're talking about allergies to pine pollen (since contact with the plant itself can be easily avoided)? Getting rid of the pines is going to make virtually no difference if there are other pines in the neighborhood or region. During the pollen season, which lasts for a couple of weeks, it can blow statewide and there's no escaping it. One's best hope of avoiding it is to stay indoors as much as possible during that time. I think you should begin with the budget because it will determine what is possible vs. what is fantasy. Re-contemplate the goals ... not how to achieve them, but simply the objectives themselves ... what activities do we want to do outside? How convenient do we want them to be? How private should it be? ... etc.