To difficult to do from a distance, but bathrooms are easy, have done many, & kitchens as well.
A few pointers. Since both bathrooms exist, keep the water closets in the same location or only a few feet away. You should save the cost of moving the main waste stack & vent. The other fixtures are plug & play but venting them will still add cost. water lines can be chased up an interior wall w/ k copper or pex. The further you extend away from the main stack, the more costs escalate. Is there a attic or crawl space above the second flood bath for a new vent connection.? Try to minimize roof penetrations. If you live in a cold climate, do not place water lines in ext wall. Window locations can also conflict w/ fixture layout.
Get a few contractor estimates. Find out if they are a broker or they have employees. How many bathrooms have they done
Call his customers, how long did the job take, issues, cost overruns, Talk to the local building inspector, what contractors always pass inspections, first time.? Complete the first room before disrupting the second. Do NOT give down payments. I never asked for them. When work is @ least 1/2 done & inspected, then some partial payment is acceptable. There are many stories of half completed jobs w/ a missing contractor. Be vigilant. Get his insurance certificates, some try to avoid a building permit, claim to save you re-assesment for property tax. That is crap, there are no secret remodels & when caught, they fine you + tear open walls for inspection. Plus you can void your homeowners policy for performing un- inspected work.