Your original contract specifies what he would do and what you would pay. If the scope of work changed OR the price changed, that would be specified in a Change Order that showed the new scope of work and the new price. It would have been signed by you. If it was me and he gave me a verbal estimate of an additional $300-400, I would pay it but you certainly wouldn't be required to do so without written authorization. Anything beyond that is crazy. It sounds like they are changing both the scope and the price. If they didn't look at the job carefully enough and missed the elevation change, they didn't do their job well enough. If they even considered building it NOT LEVEL, they are hacks.

Linnea -- This old gal has made both end-to-end and sailor course borders with bricks I got super cheap on Craig's List. The good thing about bricks is they're light weight and easy(ish) on my arthritic hands and bad back, and the work can be done a little bit at a time. First I laid out the bricks until I was happy with the overall design. This took awhile as I kept changing my mind. Then I plunged a half-moon edger on either side of each brick to make a trench, moved the bricks out of the way, popped the dirt out from the trench, threw some paving sand in the bottom and set the bricks back in place. Once it looked sorta ok I threw some more sand in the cracks and used a broom to brush it in, hosed it down and added more sand as needed. Looks just fine -- not perfect but a big improvement over nothing. Pro (ha-ha) tips: Don't make the ditch too deep because the bricks will probably settle over time. With the help of YouTube I figured out how to crudely cut bricks by hitting a straight-edge metal scraper with a hammer (emphasis on crudely). Lost a few bricks with this method but oh well. My philosophy is garden projects don't have to be perfect. I prefer to think of them as rustic. Good luck on your project!

I would work on the stairs and railings look to thin and flimsy. Broader black curving railings or adding some stone or brick on the stairs then some surrounding landscape with maybe some spreading roses would be nice. The door looks fabulous in dark gray or black! Great house but needs color and landscape maybe some vines to add a bit of depth.

If you use a polyurethane moulding (e.g. Fypon), you would need a wood cleat as a backer to attach to - so cleat on the brick, then moulding. Realize that your 'K' style gutter ("ogee") has a profile design which is meant to emulate a crown, and with no overhang to a polyurethane crown those 2 profiles will be adjacent and probably overpowering, where the profile of the polyurethane will be lost visually. Unless this is an old southern plantation with balustraded railings and acorn pediments over the windows, choosing a simple profile or none at all might be better. Building on what Tim (Charles Ross) said, it appears you have "shingle vents" specified (called out as "low profile roof vents," which could mean anything) to work with no eave overhang. First, verify you are ok with them, many people are not and for most they are a last ditch effort for venting (in this example they are installed higher than the drip edge): The shinge vent spec is an assumption though, as it seems the architect is passing the buck there. As other alternatives, there are also specific fascia vents or dormer vent styles for low venting. What may be better, is to forego a crown, and install a simple continuous linear soffit vent in the short overhang. That would provide the better attic venting. If CA, verify fire requirements for soffit venting.