Starting your own company in the IT industry can be a great venture given your extensive experience. Let's discuss the three options you mentioned - Managed Service Provider (MSP), Tech Support, and Virtual Assistant - and explore the pros and cons of each, as well as strategies for advertising, acquiring customers, and the types of jobs you can offer.

1. Managed Service Provider (MSP):
An MSP provides proactive IT support and management to businesses. This can include network monitoring, cybersecurity, data backup, cloud services, and more. MSPs typically work on a contract basis with clients, offering ongoing support and maintenance.

Pros:
- Steady and recurring revenue stream through service contracts.
- Opportunities for upselling additional services as clients' needs evolve.
- Potential for long-term client relationships and client referrals.

Cons:
- High competition in the MSP market, requiring differentiation and specialization.
- Initial investment in infrastructure and tools may be higher compared to other options.
- Requires a strong understanding of business processes and IT management.

Advertising and Customer Acquisition:
To advertise your MSP services, consider the following strategies:
a) Create a professional website highlighting your services, expertise, and client testimonials.
b) Optimize your website for search engines (SEO) to increase visibility.
c) Leverage social media platforms like LinkedIn, Twitter, and Facebook to showcase your expertise and engage with potential clients.
d) Network with local businesses and attend industry events to build relationships and gain referrals.
e) Consider partnering with other IT service providers to expand your reach.

Types of Jobs:
As an MSP, you can offer a range of services, including:
- Network and infrastructure management
- Cybersecurity and threat management
- Cloud services and migration
- Data backup and disaster recovery
- IT consulting and strategy development

2. Tech Support:
Tech support involves providing remote or on-site assistance to individuals or businesses facing technical issues. This can include troubleshooting hardware and software problems, setting up systems, and providing general IT advice.

Pros:
- Wider customer base, including individuals, small businesses, and even larger organizations.
- Lower initial investment compared to an MSP.
- Flexibility to offer both remote and on-site support.

Cons:
- Can involve high demand during peak times and potential for working outside regular hours.
- Competition from larger tech support companies or freelance technicians.
- May require continuous learning to keep up with evolving technologies.

Advertising and Customer Acquisition:
To advertise your tech support services, consider the following strategies:
a) Create a professional website outlining your services, expertise, and contact information.
b) List your services on online directories like Yelp, Google My Business, and local classifieds.
c) Offer free or discounted initial consultations to attract new clients.
d) Leverage word-of-mouth referrals by providing exceptional customer service.
e) Consider partnering with local computer stores, electronics retailers, or software vendors to gain exposure.

Types of Jobs:
Tech support jobs can include:
- Troubleshooting hardware and software issues
- Setting up and configuring systems and networks
- Virus and malware removal
- Data recovery and backup solutions
- Training and education on IT tools and software

3. Virtual Assistant:
As a virtual assistant, you can provide administrative, technical, or creative support remotely to businesses or individuals. This can include tasks like managing emails, scheduling appointments, social media management, content creation, and more.

Pros:
- Lower initial investment as most work can be done remotely.
- Flexible working hours and potential for remote work.
- Wide range of services allows you to cater to different client needs.

Cons:
- May require strong organizational and time management skills.
- Competition from other virtual assistants, freelancers, or offshore service providers.
- Building trust and proving your reliability can be a challenge initially.

Advertising and Customer Acquisition:
To advertise your virtual assistant services, consider the following strategies:
a) Create a professional website or portfolio showcasing your skills, services, and client testimonials.
b) Utilize freelance platforms like Upwork, Freelancer, or Fiverr to find clients.
c) Leverage social media platforms to showcase your expertise and engage with potential clients.
d) Join relevant online communities or forums where potential clients may seek assistance.
e) Offer a free trial or discounted initial services to attract new clients.

Types of Jobs:
Virtual assistant jobs can include:
- Email and calendar management
- Social media management and content creation
- Online research and data entry tasks
- Travel arrangements and booking
- Customer support and help desk services

Remember, the success of your company will depend on consistently delivering high-quality services, building strong relationships with clients, and continuously adapting to market demands. It's essential to thoroughly research your target market and competitors, identify your unique value proposition, and develop a comprehensive business plan before starting.

While this answer provides an overview, it's always recommended to conduct further research and seek professional advice specific to your situation and local market.