@mhatres, Consider yourself lucky today. I had a student designer who wanted to see how a design can be made with a little information. I took your floorplan for an example and made these designs for you. Hope you liked them!

Just a little ceramic information to share as a potter. Vitrified simply means the clay has become glass like by being fired to its proper maturing temperature. Usually ceramic tile means it is a lower temperature clay like earthenware or terra cotta. Porcelain is fired to the highest temperature and is more vitrified if you will. This usually means it is less porous to to absorb water and harder. Low fired ceramics with glazes much darker or lighter than the clay body will show chips easier. Rectified has to do with making the edges precise enough to fit smoothly together for less grout lines. So porcelain cost more to produce but it is more sturdy. All clay tiles should be vitrified.

Tsilanko, I would always recommend professional installation where needed. But what I am doing here is suggesting that WHEN you are planning to build or renovate, to consider how your plans will affect you in 20 or 30 years time. Split levels are very hep when you are young. A kitchen 3 steps down at 30 is rarely a problem, but might be a hazard at 60, or, as Marjie1059 suggested, if you break a leg. ... All my parents' homes were terrible for old people. They were forced to move to a bungalow in extreme old sge because the location and design of their home was more suitable for an active young couple with a large family than for an elderly couple with stroke disabilities. I would not want to move again, so my present home has features built in that make ageing in place simpler. Mostly small changes, like grab rails, and lever handles on doors and faucets. A major disability suddenly suffered requires major changes if permanent. I did look at this because it came up in the discussion, but if you look at the heading, Planning for Disability, it means just that. Plan ahead so you don't have to make expensive changes later on. But thank you for your advice, yes, major changes are not in the DIY domain.

Mohammad. I understand your program. You may be lost in the details at the moment. Please do follow and trust the advice given here by all these people. You are about to embark on a reasonably expensive journey. Get professional help with someone who you can sit down at a table and brainstorm with them your ideas and intentions. There are Architects and there are professional building designers who are members of the American Institute of Building Design (AIBD) who are well versed in projects such as yours. I personally love a design challenge. After 38 years designing homes and special use buildings I enjoy this type of challenge the most. I am in Ohio and may not be close to where you are but I am sure with a little investigation you will find the best design professional for you.