I think you first need to look at your general area and the size and style of homes there. Attend open homes and check what others have done or not done and the price they sell for. Even look at returns on leasing according to the style and condition of the house - Estate Agents will happily help you with this. Depending on movement in the market around you, this can take time, so be patient it will be worth it in the long run. You can be a little adventurous with any upgrades when people are upgrading and renovating all the time, just don't to too far with what you do or how you do it to avoid overcapitalising or limiting your market. I'm also finding a lot of buyers are resisting ultra modern homes, they like modern but not too OTT so beware of adding features that may not appeal to everyone. Again, studying the type of people in your area will give you clues as to the type of people who will want to buy into the area, the type of lifestyle they have and what they want in a home. The trend to putting ceramic tiles in kitchens and casual living areas is fading and they are much more expensive to take out and replace. Definitely not a good idea if you decide to lease as they can be broken or even pit if not cared for properly. I'm presently looking to buy a new home and I'm seeing too many homes where tiles have been destroyed which is going to be a very expensive exercise to replace. If you are going to lease, keep things simple. I think Oklouise has nailed a very simple plan although I would take the toilet from the laundry, some space from both the kitchen and living area and put a separate powder room beside the laundry so you can make it more attractive for guests. One slide-in door from the hall opening to a lobby with the laundry going off one side and the power room the other, would take care of any odours or noise. The washing machine and dryer will make noise too. I don't think I would attempt to create a master suite downstairs, I know many who agree with me on this, but dividing bedrooms over two levels tends to create "fractured" families. You certainly won't want to be running up and down stairs all night to a restless or sick toddler. It then becomes too easy to have the toddler in your room and that can be a very hard habit to break. Three bedrooms are sufficient for many people so a simple upgrading of the bathroom, wardrobes (if necessary), flooring and window covers should be all that is necessary for the upstairs. The emphasis these days seems to be more in living space and entertaining especially when it includes generous outdoor areas , so I would make that your priority.

using approximate metric dimensions my initial suggestion would be to move the kitchen into the "upstairs" (with or without keeping the old opening) use the old kitchen as a hobby, media, study, guest room with sofa and wide desk, use the stairwell space for a mini laundry and rearrange the bathroom and toilet to include extra space out of the hallway to allow for more generous vanity and shower with extra handbasin for the toilet but need to know location of all windows and views to suggest best arrangement for kitchen, dining and lounge, remove the old fire from the entry, retain the original storage and add a set down table, seating and or small desk with charging stations and reverse the front door to open towards the living area but, something like this should work without spoiling the original house and make sure that new kitchen and bathroom is styled to suit the timber with vintage colours and, if the sliding doors shown in the plans are not cavity sliders, replace doors with plain hinged doors

please include a site plan showing the house with distance to all boundaries and some photos including a google earth image of the roof would also help

It’s for holidays. It’s for us, plus two small kids. We would like to have a space for guests too (even if informal and not a proper room). We would like to be able to work from home too. We currently use the third bedroom as a study/junk room (due to lack of storage). We have one baby who used the second bedroom and plan on having a second child but would be open to them sharing. We had also thought about potentially putting a granny flat on the block as a study pod