Look for developers with 2-5 years of experience in blockchain platforms like Ethereum, Hyperledger, or Solana. They should have proficiency in languages like Solidity, Rust, or Vyper, along with experience in smart contract development, dApp integration, and security best practices. Certifications from recognized platforms and a strong GitHub portfolio are also important indicators of expertise.

The cost varies based on experience level and location. Entry-level developers typically earn $100,000-$130,000 annually, mid-level developers earn $130,000-$180,000, and senior developers in tech hubs like San Francisco or NYC can earn $180,000-$200,000+. Freelance rates range from $80-$200 per hour depending on expertise.

An average blockchain project takes 3-6 months to complete, including discovery and strategy (2-4 weeks), design and development (6-12 weeks), testing and optimization (2-4 weeks), and launch and deployment (1-2 weeks). Complex enterprise solutions like Hyperledger-based supply chains may require 6-9 months.

Priority platforms include Ethereum (for DeFi and NFTs), Hyperledger (for enterprise private blockchains), and Solana (for high-speed, low-cost applications). Experience with Polygon and Binance Smart Chain is also valuable. The choice depends on your specific use case and business requirements.

Verify qualifications through GitHub portfolio reviews, certification verification (Blockchain Council, Coursera), technical assessments on platforms like HackerRank, technical interviews covering consensus mechanisms and cryptography, reference checks from prior employers, and background verification of employment and education history.

Ongoing maintenance includes continuous security monitoring and vulnerability checks, quarterly security audits, performance optimization and scaling, platform updates for Ethereum/Solana, bug fixes and patches, user support for dApps and wallets, and compliance checks. Expect to budget 10-20% of initial development costs annually for maintenance.

This depends on your project scope and duration. Full-time developers are better for long-term projects requiring ongoing development and maintenance. Freelancers are ideal for specific projects with defined timelines and deliverables. Consider using platforms like Toptal, Upwork, or Braintrust for freelancers, and LinkedIn or specialized recruiters for full-time positions.

Beyond technical skills, look for adaptability in the evolving blockchain landscape, strong problem-solving abilities, effective communication skills for explaining complex concepts, team collaboration capabilities, and cultural fit with your organization's values and innovation goals.

Key deliverables include a customized project roadmap, prototype proof of concept, secure smart contracts, integrated wallet or DEX, comprehensive deployment documentation, user guides and training materials, security audit reports, and complete source code with repositories.

Ensure security by hiring developers familiar with security best practices, conducting thorough smart contract audits, implementing cryptographic encryption and distributed consensus, performing regular vulnerability assessments, maintaining compliance with regulations like HIPAA, and establishing 24/7 monitoring systems post-deployment.