Nobody will give you definitive advice from a photo. The only way to be certain is to get a professional up in the roof space to see if it is a trussed or raftered roof, and where these loads come down. If it was built when the house was built there won't be ceiling plaster above it. If it was added in later (after the house was built) then there may be ceiling plaster above it, in which case it is proabably not load bearing. Best of luck, Dr Retro of Dr Retro House Calls

always depends on surprises eg is there any asbestos in the walls and floor (with asbestos add extra thousands) and think about how furniture will be arranged ....would removing the whole wall give you any better furniture arrangements and consider moving the new master bedroom door to open in the bathroom hallway (and close up the other two doors but how would you patch the walls, floor and ceiling if the whole wall is removed...what are the walls and ceiling lined with and are there plaster cornices and decorative ceilings?... you will need an electrician to remove the existing wiring to make it safe for demolition and then come back later to install the new light switches and good time to add an extra power point or two... say two half days about $1000, a carpenter to safely demolish and rebuild anything that needs extra support, fill in and open up new doorway, rehang recycled old door, add architraves and patch skirting boards...maybe two days if you can help with demolition and rubbish removal and cost say $2000, a plasterer to repair plaster walls and ceilings say $1000 although a carpenter can usually do minor platerboard repairs and maybe $500 to repaint the new rooms if you do all the work yourselves plus whatever floorcoverings need to be replaced ...so expect about $5000 - $10,000 assuming no major problems ..but only a quote for your job will be sure

my suggestion has the bathroom at the end without any changes to other walls, door or windows and i've include furniture to suit young long term student tenants and this could be altered to suit other guests...all the furniture, cabinets and fixtures are based on readily available flat pac options like Ikea and Kaboodle and the only custom carpentry will be the new bathroom wall and storage under the stairs and the usual trades for plumbing and electrical etc and i would use a shower cubicle rather than tiles so that you could use continuous vinyl flooring throughout the whole flat and minimise tiles...careful choices of all fixtures and fittings and maybe some basic DIY from your daughter and her boyfriend to assemble flat pacs and with painting? should allow the renovation within your budget and don't forget an outdoor sitting area with decking boards, outdoor furniture and a pullout clothesline rather than a dryer

my suggestions includes moving the sliding glass doors into the dining room, has a small walk in pantry and open scullery to avoid blocking the new window, keeps the separate entry foyer wall (to help support upstairs) adds a vanity to the powder room, removes the extra shower to make the laundry more functional and reversing the stairs (depending on upstairs floorplan) would make for easier access for moving furniture, adds more light from the stairwell into the entry foyer and the under stairs storage space could be included in the bathroom for more space but all suggestions depend on accurate dimensions