HVAC Mechanical Designer Needed: Complete Manual J/S/D for 5,956 SF New Build Home (IAQ Focused)

We are looking for an experienced residential HVAC designer or mechanical engineer to complete a comprehensive load calculation and duct design package for a new custom home build. The house features a total of 5,956 sq ft of finished, conditioned living space, plus an unfinished basement and an attached garage. The homeowner is highly focused on Indoor Air Quality (IAQ) and system performance. Project Scope & Specifications: * Manual J, S, and D: Complete room-by-room load calculations, equipment matching, and duct sizing using ACCA-approved software (Wrightsoft or Elite RHVAC preferred). * Deliverables: Professional PDF summary reports and a 2D line duct schematic overlay directly onto the provided 1/4" scale blueprints. System Configuration & Equipment Constraints: 1. Two-System Layout: Heating fuel will be Propane. Equipment line will be American Standard two-stage, variable-speed furnaces. - System 1 (Upper Level): Dedicated to the 2,231 sq ft finished second floor. This is an entirely attic-based system. Supply registers will be ceiling drops, and return grilles will be located high on interior walls near the ceiling line. The furnace/air handler MUST be located within the dedicated 2nd-floor furnace room shown on the prints. - System 2 (Main Level & Lower Level): Dedicated to the 3,725 sq ft finished first floor and the unfinished basement footprint (structural load only). Propose an optimal basement furnace location tucked away to preserve future finishing potential. 2. Filtration: Both systems will utilize 4-inch high-MERV media filters. Duct design must account for this static pressure drop. 3. Duct Material: 100% rigid sheet metal trunks and branch runs (no insulation duct board). 4. Attic Duct Insulation: System 1 rigid sheet metal attic trunk lines will be encapsulated with a minimum of 2 inches of closed-cell spray foam (R-13+ insulation value). Please input this duct insulation performance parameter. 5. Ventilation (ERV): The design includes an Energy Recovery Ventilator. Please design this with a dedicated, independent ductwork layout (separate from the main HVAC trunks) to pull stale air from high-odor/moisture zones and supply fresh air directly to bedrooms/living areas. 6. Outdoor A/C Placement: Both outdoor AC condensers must be located on the Left Elevation (South side). Note that this side is highly constrained with electrical mains, a basement window, a future generator, and future pool equipment. Condensers may need to be staged out into the side yard/property line slightly to maintain code clearances. What I Will Provide: * Full architectural floor plan blueprints (PDF, 1/4" scale) including Foundation, 1/1, and 2/1 layouts, plus exterior elevation views showing windows. * Build site zip code / location and exact compass orientation. * Target R-values and window U-factor/SHGC specs. Budget & Revisions: Budget is set at $350 fixed-price as a starting point, but I am open to discussing the final milestone amount based on your review of the architectural blueprints. Proposal must include one free round of minor adjustments in case building material specifications shift slightly during the framing phase. To apply, please share examples of previous residential Manual J/S/D design packages you have completed using Wrightsoft/Elite, along with your typical turnaround time.