I just did a bath remodel in Philly. I had estimates all over the map. Most were in the $32-42K range (but those subcontracted out a lot of the more specialized labor (i.e., tiling, electrical, plumbing) and charged what appeared to be a 25% mark up on all materials). I ended up going with a highly recommended contractor, but having to buy all of my own materials. My bathroom is about 110 square feet and the total remodel cost was $10,750, and the finish materials were an extra $15K (contractor supplied the copper, pvc, shower liner, thin set and mortar, lumber, hardibacker included within his price). It took 18 work days. Having to buy all of the materials in a pain and took a lot of time; I guess that explains the reason for the mark up many charge. For some reason, it's not letting me post the link to my post on my remodel. You can find it if you'd like to, or just use this: http://ths.gardenweb.com/forums/load/bath/msg0409041521118.html?10

Well in our case we decided to abate asbestos which was literally everywhere..and we knew it'd get disturbed since we bought the house knowing we'll go for an addition(very naive then of course as to how much it's cost and how long it takes..well we found out LOL.) But yes freeoscar, absolutely so. we also had to do things we didn't plan on doing because they started looking especially bad when surrounded by new..dragged everything down the only place we touched minimally-was kids' bath. the sellers remodeled it somewhat recently..two walls of tiles, which I disliked but asbestos was safe there, and to redo that bath fully would be another 10-12 K materials not included so we took down non tiled walls only, improved storage, did cosmetic things..I poured hours of thought into this bath to make it look like it belongs to the house, and make it interesting, and at the same time to be very functional. then we got a slab leak there (the only old drain in the house) right after we moved in so another thousand and a half $ down the drain..pun intended lol also I was highly flattered when one of my friends who's successfully building her second career as a photographer recently asked me to come and shoot my house for her portfolio and she shot all the rooms but this bath. she said in this turning- to be-not-excited voice "umm..it's fine..but I don't think I need pictures of it..." so now I'm all sad:)

What's the age of your propery? bought a (smaller) ranch in 2014, with an intetion to add (we added just 200 sq feet). U-shaped. Alliowed us to add a big master bathroom, master closet, etc. But. Built in 1968 or 1970..things add up. Asbestos remediation. It's okay to have asbestos-it's not ok to disturb it once remodeling. Asbestos was practially everywhere. Whatever you move/reconfigure/touch..flooring-needs to be redone. HVAC-all new HVAC. Plumbing-was already easier to do all new plumbing (didn't move things around, added them, yes) . Was no insulation in the house, at all-all new insulation. Roof-had to be partially redone. New kitchen.. Electrical had to be added, etc. Sounds a lot like your project. (unless you choose to do just one out of three things. we also thought we'd do addition only. didn't work that way. it starts 'creeping", once you open the walls etc) Then backyard had to be at least partially redone(we took a break, 'cause whole story took us two years. Tackled it only last year. Nothing fancy, except I did go for a nce tile, to keep in character with the house) While remodeling we saved tons of money by hunting vintage/open box..but not time or nerves. It's So Cal here-so to add plans, permissions, 6 inspections, huge dumpster, port-a-potty on premises(the port-a potty company were the ones always on time lol. The smoothiest part of remodel.)... The house was 1675,sq f and became 1875 sq feet. Nothing special. Was a modest ranch in nice area, stayed a modest ranch in nice area. More congruent with itself than it was. Partially closed off kitchen, added closets, didn't move structural walls. Did splurge on some custom tile and custom cabinetry given kitchen is pretty small. So..I don't know about 800K. But if I'm honest with myself.(and I really dont want to be, lol) .it can be 400K. Everything together, Depending on whether you choose to do all three, and your local costs, and what does it entail in YOUR house, Our contract was cost plus type. I agree to start with people who build homes in your area. Get several opinions. To get the idea. We had several opinions -and they were almost all pretty much similar ballpark. we chose by chemistry, and willingness of GC s to even deal with us/our project. Not everyone wants dealing with additions unless they're fairly easy additions only. Where no or minimum remediation involved, no other things inside, etc, I must add that the best part of our remodel , after all, was the addition. it's so seamless nobody can't find it, nobody who even knows the story. Nobody remembers that's why we started remodeling in the first place, but it turned to bedown to studs remodel, and it was more complicated than bullding new, I think. The money won't be recoupable (even though the prices right now are crazily up-but that's the market..nothing to do with our remodel. remodel adds value of course, just maybe a half of what we spent. On a good day.) Time and nerves..for sure not recoupable. It might be still worth it, the learning curve, you'll get for sure. And maybe better home for your family, both in terms needs and wants, Having written all that long post..your house can be younger, with less problems, less surprises.., you might decide on smaller project out of three, etc, etc. Do use pros if decided to move forward-whether architect, or designer..we didn't, wanted to save money...I acted as my own designer (with DH's help of course), and it was 24/7 job. Exhausting. Unfortunately I found these forums when I was well into remodel already. Use them too. ETA: sorry for the typos

@Tim Cleary It sounds like a straightforward bump-out, tie-in the foundation, typical frame, and tie-in the roof. He didn't post any pictures so I envisioned something that is very common around here. These types of additions going up in every town, you can do them in your sleep. As the drawings go, they usualy done on 2-4 pages. You have a foundation and floor plans, typical cross-section, everything is indicated on there, if needed a few section details if something structural involved, etc and some typical general notes which pretty much copy and paste on it, etc. Some architects like to blow it up a bit, and they will copy and paste all kinds of things on the drawing,i.e code tables, hanger tables, joist span tables, and the kitchen sink, and spread it across 10 pages... Sometimes times I do plan review for a homeowner half of the information on it belongs to a different house. I saw you mention before that some want to charge a % of the cost, in 30+ years I ran into one of them when he told me that I told him how about you give me 1/2 of the construction cost, do the drawings for free and you can be my partner. Builders around here don't deal with architects like this or who charge per/hr, guys like this are looking for a cow to milk, and unfortunately, they nail some homeowners.