1905 home replacing HVAC advice

I have a 1905 home in Seattle that is 2800 square feet finished space, with an unfinished partially heated basement. The house has a finished attic we use for home office a guest room when relatives come over.

There is existing 8" (?) duct work run all over the house by previous owner. Probably done within last 10 years (the ducts look really new).

We have vents in every room but not ones that can be closed. Example: https://imgur.com/a/isdIg

Our existing gas furnace is a super old 40-50 year old unit that is 65-70% efficient. It's also way over sized at 165k BTU. Previous owner got it for free as he was a city contractor.

When it runs, it is so loud we can hear it and the vent noise. It also runs for very short periods of time. I've been told this is a classic sign of oversized and inefficient equipment.

We've had to do several repairs on the unit last few months. Given our high heating bills and our desire to get AC for the house, we are looking to phrase everything.

I know very little about HVAC and called several companies to come look at our house and quote something. The recommendations have been all over the map with equipment ranging from 40k To 80K BTU. One company was here for maybe 30 mins before providing a recommendation.

Not a single one has done a manual load calculation from what I can tell. First question Is whether this a danger sign in itself and if I should only go with a place that does one? One vendor I asked about this said that he could do one but he's got a lot of experience with old homes like mine and after what he saw he's comfortable making a recommendation.

The recommendations I've had so far are:

Company 1 Did no load calculation. Was on site for maybe 25 mins.

1. Mitsubishi Ducted Heat Pump System - $10k Outdoor unit#-MXZ3C30NA2-U1 Indoor unit#-MVZ-A30AA4

2. Trans XT95 Gas Furnace with AC Unit - $10k

Company 2 Unclear if they did load calculation. He did some measurements, and i’m clarifying with him now whether they have a Manual J and to share it with me.

1. Mitsubishi Air Handler (PVAA30AA4) + Mitsubishi H2i heat pump (PUZHA30NHA4) $15k
2. Mitsubishi 4 zone ductless $14.5k

company 3 No load calculation.

1. American Standard 85% Platinum 80k BTU gas furnace + variable speed heat pump + “ACONT 824” thermostat - $16.5k
2. Mitsubishi 42k heat pump + “indoor air handler” + 12k indoor wall unit in master bedroom + 12k indoor wall unit for finish attic - $15k

I had company4 come out and they seemed to know more stuff and were more thorough. Thye asked for the energy audit results I did and said they could do their calculations offsite based on information provided by the city on floor plans.

Company5 i have coming out in 7 days.

Any interim advice?

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