Investor profile - FL
William Seider
William Seider is a real estate investor and operator based in Sarasota-Bradenton, FL. Public filings show activity across 2 properties held through 3 holding companies. Recent mortgage relationships include Northern Trust and Wells Fargo Bank.
William's Activity
As of December 2025, public records show approximately $750k in recorded mortgage exposure linked to this investor across at least 2 mortgage filings and 2 properties held through 3 holding companies. Activity appears concentrated in residential assets recorded between 2015 and 2019.
Primary Geography
Sarasota-Bradenton, FL
ZIP codes: 34234 and 34236
Most recorded activity for this investor appears in SARASOTA.
Property Type Breakdown
Associated Entities (3)
FL · 2 properties · 2 mortgages
FL · 4 properties · 0 mortgages
FL · 2 properties · 0 mortgages
Mortgages (2)
| Date | Amount | Status | Lender | Borrower | Address |
|---|---|---|---|---|---|
| 09/04/2019 | $750k | Open | Northern Trust | CROSS STREET REAL ESTATE SERVICES LLC | 457 JACKSON DR, SARASOTA, FL 34236 |
| 04/10/2015 | $5.0M | Closed | Wells Fargo Bank | CROSS STREET REAL ESTATE SERVICES LLC | 374 S SHORE DR, SARASOTA, FL 34234 |
+0 more not shown
Owned Properties (2)
| Address | Deeded owner | Status | Consideration |
|---|---|---|---|
| 457 JACKSON DR, SARASOTA, FL 34236 | CROSS STREET REAL ESTATE SERVICES LLC | Owns - 6.5 yrs | $1.0M |
| 374 S SHORE DR, SARASOTA, FL 34234 | CROSS STREET REAL ESTATE SERVICES LLC | Sold | $9.0M |
+0 more not shown
FAQ
What type of real estate does this investor focus on?
Associated mortgages and deeds show activity in residential properties across Sarasota-Bradenton, FL.
What companies is William Seider associated with?
William Seider is associated with 3 entities based on extracted signatures from public records. Key entities include CROSS STREET REAL ESTATE SERVICES LLC, WMS PROPERTIES LLC, and PTW STASSNEY LLC.
How many properties are associated with this investor?
At least 2 properties are associated with William Seider and the entities they control, based on signatures extracted from recorded documents connecting William Seider to the entities.
Which lenders has this investor worked with?
Recent mortgage activity references Northern Trust and Wells Fargo Bank, indicating a mix of lending relationships.
How recent is their activity?
Records show activity from 2015 through 2019, with the most recent mortgage recorded in 2019.
How is associated activity determined?
Elementix uses AI to extract signatures from recorded documents. These signatures are used to determine the relationships between people and entities. This is a novel approach that goes beyond looking at corporate filings and skip-tracing.
The information displayed on this page is compiled from recorded real estate documents, business filings, and other lawfully available sources. Elementix summarizes and analyzes public record activity related to investment real estate and associated business entities. Any contact indicators shown (such as email domain references or partial phone digits) are provided solely as unverified signals and may be incomplete or outdated.
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